Car shut off, why?

[DMC81]

I went out and started my car today just to get the juices moving in her and setting at idle for about 5 min. it shut off. No warning, no hick-up, no stutter, it just died and would not restart. I know there are many things that could cause this I'm sure but what comes to mind to the veterans on here? Thanks.

[DMC5180]

Top 2 reasons

Fuel pump died.
Loose connection on the ignition resistor.

[Cory W]

Additional reason: Inertia switch melting/wiring (which would stop the pump, going along with what Dennis said)

[thirdmanj]

Were you able to restart her at all?

[DMC81]

The pump is still running but I didnt get to dig in to tho, its to dark and cold but I will check the resistor tomorrow. I was thinking a wire issue but was not sure.

[DMC81]

Were you able to immediately restart her? Or did you have to wait a bit? Is she not starting at all now?

Nope it would not re fire at all.

[thirdmanj]

Nope it would not re fire at all.

My money would also be on the ignition resistors. 1258 had a similar problem a few years back, and they were corroded as hell. Turns out a little cleaning and she was back to tip top form.

[DMC81]

My money would also be on the ignition resistors. 1258 had a similar problem a few years back, and they were corroded as hell. Turns out a little cleaning and she was back to tip top form.


James,

Mine looks original should I go ahead and get a knew one regardless?

[Spittybug]

James,

Mine looks original should I go ahead and get a knew one regardless?

No. Finish diagnosing before dispersing cash.

[thirdmanj]

No. Finish diagnosing before dispersing cash.

Agreed.

[DMC81]

No. Finish diagnosing before dispersing cash.

Do the resistors even go bad unless it dropped?

[Spittybug]

Do you have a meter? Just measure the resistance across them. But no, generally speaking resistors do not just go bad.

Fuel
Air
Spark


If you hear the fuel pump going, then chances are you haven't had a catastrophic blockage that would prevent fuel from reaching injectors.
Air.... did your throttle cable perhaps snap and shut your butterflies?
Spark. Most likely culprit. Pull a plug wire and have someone crank car while you see if a spark jumps from the end of the lead to the engine (anywhere, about 1/2 inch away). Use gloves.

Once you figure out it is spark (my guess), report back and we'll continue.

[DMC81]

Do you have a meter? Just measure the resistance across them. But no, generally speaking resistors do not just go bad.

Thanks guys, I'll do some checking here in a day or so...it's going to be very cold here for a day or two. lol

[DMC5180]

Do the resistors even go bad unless it dropped?

Never heard of a truly bad one. It's just the wire terminal connections that can cause problems.

[Jonathan]

Definitely not trying to be a smarta$$ here, but there is fuel in the tank, right?

[DMC81]

Definitely not trying to be a smarta$$ here, but there is fuel in the tank, right?


Yes Sir. It's got fuel but I'm glad you asked. I'm still so new to the Delorean that I wouldn't put it past my self..lol jk

[Rich]

Nope it would not re fire at all.

As noted in other troubleshoot-assist threads, it's important to be sure we know your car's symptoms clearly.

Please confirm the status after the car died for no apparent reason during the warm-up idle episode the other day:

- Fuel is in tank
- Fuel pump is heard running/priming, even if only momentarily, when key is turned to ON position before a new cold start attempt (fuel pump OK)
- Engine cranks normally (starter system and battery OK)
- Engine does not start/run

[Rich]

The DeLorean factory did supply a few pages of troubleshooting guidance for an Engine Does Not Start condition:

LINK: Factory-Troubleshooting-Charts-Engine-Will-Not-Start (http://dmctalk.org/showthread.php?3142-Factory-Troubleshooting-Charts-Engine-Will-Not-Start)

No guess as to whether these factory docs are better than 30 years of experience/advice from this forum.

If you don't feel confident or run out of patience just get it to a decent indep. mechanic. The DeLorean isn't exotic or unusual in this respect even if it might be new to you. Good luck.

[DMC81]

Will you hear the fuel pump prime every time you turn the key? For example if I turn the key on and hear the pump run then turn the key off and do it again should I hear it run again after just doing it once?

[DMC5180]

Some RPM relays prime the fuel pump some don't. The Delorean used both versions. There is a solid state (aftermarket) unit that has a prime feature. It will prime every time you cycle the key. Not sure about the OEM ones that prime.

[DMC81]

Some RPM relays prime the fuel pump some don't. The Delorean used both versions. There is a solid state (aftermarket) unit that has a prime feature. It will prime every time you cycle the key. Not sure about the OEM ones that prime.

That is a good piece of info to know, is it better to have it one way over the other tho?

[jorge figueroa]

Several weeks ago one of our delorean
had a similar problem
checked the fuel pump, ignition system
and found that the relay of the fuel pump
had several components detached (bad solder)
A common problem in European cars, especially Volvos
talk a lot about this topic in the discussion forums dedicated to Volvos
but never mentioned in the discussion forums dedicated to delorean
Sometimes the problem is in plain sight, but in other cases you have to use a magnifying glass
to see how this welding on the electronic panel in the relay
I managed to fix this problem in some DeLoreans

[DeLorean03]

Honestly not trying to give you a hard time, but you should come to our Thursday night get-togethers down in Cincinatti.

We constantly have at the very bare minimum 4-6 of us there every single Thursday. Ken's place currently has 8 DeLoreans there in winter storage/being worked on including mine (storage). Just in case you don't know, Ken runs the national DeLorean show over at deloreancarshow.com ... he's very helpful and knows these cars pretty darn well.

I met your father in the Home Depot parking lot at Col Glenn Hwy right in front of Quaker Steak. He gave me your number, and I unfortunately lost it. You are more than welcome to call me. I told Ken about you, and he said he'd be willing to bring your car down on a trailer to get it to his place for us to help you (you two work out the details on the flatbed arrangements).

Seriously dude, you got a BIG club right here and a lot of people willing to help. Here is a picture of the club at our first meeting just this last Saturday - 49 people and 6 cars showed up - in January: https://sphotos-b.xx.fbcdn.net/hphotos-snc6/230642_10152418468735696_1277703082_n.jpg

Just extending the offer out there. I'll PM you my number.

- Jeremiah

[WelmoedJ]

Do you have a meter? Just measure the resistance across them. But no, generally speaking resistors do not just go bad.

Fuel
Air
Spark


If you hear the fuel pump going, then chances are you haven't had a catastrophic blockage that would prevent fuel from reaching injectors.
Air.... did your throttle cable perhaps snap and shut your butterflies?
Spark. Most likely culprit. Pull a plug wire and have someone crank car while you see if a spark jumps from the end of the lead to the engine (anywhere, about 1/2 inch away). Use gloves.

Once you figure out it is spark (my guess), report back and we'll continue.

If there's no spark, check the connector in the wire from resistor pack to the starter relay next to it (the yellowish transparant covered one).
That's more than once the bugger!

[DMC81]

If there's no spark, check the connector in the wire from resistor pack to the starter relay next to it (the yellowish transparant covered one).
That's more than once the bugger!

I will look the all over, seems to be what most people are thinking. Thanks buddy.

[Dangermouse]

Top 2 reasons

Fuel pump died.
Loose connection on the ignition resistor.

Add:

Loose connection on the ignition coil (in my case anyway it had vibrated off)

[DMCMW Dave]

Add:

Loose connection on the ignition coil (in my case anyway it had vibrated off)

Yeah - that would be #3.

[Bitsyncmaster]

Another item to check is your two pin connector on the ignition distributor pick up coil wire. Mine was so badly corroded, I cut it off and soldered the wires without a connector.

[DMC81]

Another item to check is your two pin connector on the ignition distributor pick up coil wire. Mine was so badly corroded, I cut it off and soldered the wires without a connector.

Thanks Dave, I'll make sure I check it out. Right now these 10 degree temps outside are putting a hold on going out in the garage. (not heated) lol

[DMC81]

Good news!!! I went over the things you guys suggested, I wire brushed the terminals on the ignition resistor and tightened up the female connecting wires. I did the same on the ignition coil and then removed the coil wire it's self and reinstalled it just to make sure it was making good contact. I'm not sure which one was the problem but it fired right up and it was running much smoother and better!!! I let it run for a good while till it was up to temp and it never even hinted at shutting off. Thanks for all the info on this problem guys!

[Nicholas R]

Good news!!! I went over the things you guys suggested, I wire brushed the terminals on the ignition resistor and tightened up the female connecting wires. I did the same on the ignition coil and then removed the coil wire it's self and reinstalled it just to make sure it was making good contact. I'm not sure which one was the problem but it fired right up and it was running much smoother and better!!! I let it run for a good while till it was up to temp and it never even hinted at shutting off. Thanks for all the info on this problem guys!

So that means you're going to come down to Kens tonight right? Its really a shame if you dont. You'd be amazed at what you can learn in even one night. You and DeLorean03 are practically neighbors; give him a call.

[DMC81]

So that means you're going to come down to Kens tonight right? Its really a shame if you dont. You'd be amazed at what you can learn in even one night. You and DeLorean03 are practically neighbors; give him a call.

I do want to get down there with you guys as soon as I get a chance. I work kinda late tonight so it just wont work. I have been talking with DeLorean03 some and the funny thing is we work at the same place..lol Thanks for all the help as always Nick.

[DMC81]

Well I thought I had it fixed, I started the car today and it ran for about 10min. and shut off again. I didnt have a way to check for spark at the time but is there something that would cause the car to die after it gets warm? It was not to full temp yet when it died it was at the same temp as when it did it the last time. Would a relay cause this issue maybe?

[WelmoedJ]

1. If you haven't yet checked the internal of your RPM relay, do so.

2. Did you check the wire connector near the fuel pump and the connections on the pump itself?

3. You could run a 12V wire directly to the pump's positive connector and see if your car keeps running.
If it keeps running it's something (wiring, circuits (RPM relay), ground in this area.

4. Check your distributor, the pickup coil inside may be defective or the contacts in the wiring to the ECU bad/dirty, rotor etc..
This only is true if you do not see sparks regularly coming from a spark plug wire (as expected).

[David T]

If it warms up and dies after about, say 20 minutes, I would check for spark. This seems to be a common symptom for a bad impulse coil in the distibutor.
David Teitelbaum

[DMC81]

1. If you haven't yet checked the internal of your RPM relay, do so.

2. Did you check the wire connector near the fuel pump and the connections on the pump itself?

3. You could run a 12V wire directly to the pump's positive connector and see if your car keeps running.
If it keeps running it's something (wiring, circuits (RPM relay), ground in this area.

4. Check your distributor, the pickup coil inside may be defective or the contacts in the wiring to the ECU bad/dirty, rotor etc..
This only is true if you do not see sparks regularly coming from a spark plug wire (as expected).



If I take the pannel off the fuse and relay area should I hear the RPM relay click when I turn the key? I noticed this when I retried to start it.

[DMC81]

I heard that the way to tell if the impulse coil is bad if i crank the engine and the tachometer does not move then that is the problem. Is this a good way to test it?

[Bitsyncmaster]

1. If you haven't yet checked the internal of your RPM relay, do so.

2. Did you check the wire connector near the fuel pump and the connections on the pump itself?

3. You could run a 12V wire directly to the pump's positive connector and see if your car keeps running.
If it keeps running it's something (wiring, circuits (RPM relay), ground in this area.

4. Check your distributor, the pickup coil inside may be defective or the contacts in the wiring to the ECU bad/dirty, rotor etc..
This only is true if you do not see sparks regularly coming from a spark plug wire (as expected).

These are the most common faults that should be done even if your car has no problems. Heat will show up bad connections at random times.

[DMC81]

These are the most common faults that should be done even if your car has no problems. Heat will show up bad connections at random times.

If i crank the engine and the tachometer does not move does that indicate a bad impulse coil? Is this a good way to test it?

[Bitsyncmaster]

If i crank the engine and the tachometer does not move does that indicate a bad impulse coil? Is this a good way to test it?

I would think that is a good way to see if the ignition unit is working (includes the pickup coil and ECU). It still may not show you your problem with the engine unless you still have the problem when doing this test.

[DMC81]

I would think that is a good way to see if the ignition unit is working (includes the pickup coil and ECU). It still may not show you your problem with the engine unless you still have the problem when doing this test.

I went and cranked it and the needle didn't move at all.

[Bitsyncmaster]

I went and cranked it and the needle didn't move at all.

I'm not home this week so maybe some others can try that test.

[DMC81]

I'm not home this week so maybe some others can try that test.

As always, thanks for your time and info Dave. Always a big help.

[Nicholas R]

I went out and watched my tach while running the starter and the needle sat right around where I assume 100-150rpm would be. (about an 1/8th of an inch from where the needle rests). Not sure whether or not that helps since my tach signal is generated by the ECU and converted from 8cyl to 6cyl, and my starter is quite a bit different. However; there is no reason why there wouldn't be the same number of pulses to the ignition coil on a PRV.

The tach signal comes from the negative side of the ignition coil. If you want to see whether or not your coil is firing while the starter is turning, you could put one of these inline:
16902
A few dollars at harbor freight^

Or really you could pull a spark plug out, leave the wire attached and lay it on the intake manifold. If it sparks you know the system is working. If you get nothing, you know somethings not working, whether ignition coil, pickup coil, cap, rotor, etc. At that point just work your way backward through the system, seeing what isnt working.

[DMC81]

I went out and watched my tach while running the starter and the needle sat right around where I assume 100-150rpm would be. (about an 1/8th of an inch from where the needle rests). Not sure whether or not that helps since my tach signal is generated by the ECU and converted from 8cyl to 6cyl, and my starter is quite a bit different. However; there is no reason why there wouldn't be the same number of pulses to the ignition coil on a PRV.

The tach signal comes from the negative side of the ignition coil. If you want to see whether or not your coil is firing while the starter is turning, you could put one of these inline:
16902
A few dollars at harbor freight^

Or really you could pull a spark plug out, leave the wire attached and lay it on the intake manifold. If it sparks you know the system is working. If you get nothing, you know somethings not working, whether ignition coil, pickup coil, cap, rotor, etc. At that point just work your way backward through the system, seeing what isnt working.

Good call Nick I'll have to go pick one up and take a look.

[Jonathan]

I went and cranked it and the needle didn't move at all.

Mike,

Are you trying to determine what a "normal running" DeLorean tach needle does when you start the engine?

If you are, I have a couple videos on YouTube for before and after my exhaust manifold gaskets were installed that show the engine being started at the beginning of the video as well as being turned off at the end. Search "Canadian DeLorean" and you'll see them. My tach needle is doing (briefly) what Nick described at 100-150 RPM or so (it's quick though).

[DMC81]

Mike,

Are you trying to determine what a "normal running" DeLorean tach needle does when you start the engine?

If you are, I have a couple videos on YouTube for before and after my exhaust manifold gaskets were installed that show the engine being started at the beginning of the video as well as being turned off at the end. Search "Canadian DeLorean" and you'll see them. My tach needle is doing (briefly) what Nick described at 100-150 RPM or so (it's quick though).


Thanks Jonathan, I just checked the vid. Looks good, now I have something to go off of.

[KMC-DMC]

Well I thought I had it fixed, I started the car today and it ran for about 10min. and shut off again. I didnt have a way to check for spark at the time but is there something that would cause the car to die after it gets warm? It was not to full temp yet when it died it was at the same temp as when it did it the last time. Would a relay cause this issue maybe?

I had a similar problem a couple of years ago.
The car would start and run for about 10mins and then shut down for no reason.
It would not re-start and there was no spark.
Wait about half hour and the car would start up again, then after 10mins or so would shut down, again no spark.

Reason - Impulse coil on distributor. When the engine got warm it effected the coil and interrupted the spark distribution.

[DMC81]

I had a similar problem a couple of years ago.
The car would start and run for about 10mins and then shut down for no reason.
It would not re-start and there was no spark.
Wait about half hour and the car would start up again, then after 10mins or so would shut down, again no spark.

Reason - Impulse coil on distributor. When the engine got warm it effected the coil and interrupted the spark distribution.

You said it, that's exactly what it does! I will replace it as soon as I get a chance. Thanks for the info.

[DMC81]

Ok, I know it has taken me for ever to get everything in the valley back together but it finally is. So I go to start it up, I hear the fuel pump and after a few cranks it fires and runs for a few seconds then dies. I repeat a few times and it fires again, runs for a few seconds and dies. Now I cant it to fire at all so I checked and I'm getting spark and fuel. I replaced the impulse coil when I had it out so now what do I check next is my question?.....:what_the:

[Bitsyncmaster]

Try jumpering the RPM relay and see if that keeps you running. You can not leave the jumper installed after your test or you will run the battery down.

[DMC81]

Try jumpering the RPM relay and see if that keeps you running. You can not leave the jumper installed after your test or you will run the battery down.

Dumb question but what is the jumper doing, running fuel pump continuously?

[Delorean Industries]

Dave is correct to make sure that the fuel supply is constant. Next question would be: Have you made any adjustments to the air fuel mixture? Removed the fuel distributor completely from the air metering housing? If the fuel mixture is off in any way this can happen as well.

[DMC81]

IT"S ALIVE!!!!! wow that was like the highlight of my day....I put the paperclip in, hit the key and boom she fired right up with just a slight hesitation. Rock on! Thanks guys!!:thumbup:

[DMC81]

Dave is correct to make sure that the fuel supply is constant. Next question would be: Have you made any adjustments to the air fuel mixture? Removed the fuel distributor completely from the air metering housing? If the fuel mixture is off in any way this can happen as well.

It is running rough still, Is this something that could be causing that? If so how do I go about adjusting it?

[Delorean Industries]

It is running rough still, Is this something that could be causing that? If so how do I go about adjusting it?

At the very least you need a dwell meter for this. Best case an air fuel meter. How far did you have the top apart? Did you pull everything off together? IE the metering housing with everything still attached? OR did you remove each individual component. If you have everything together right and did not pull the metering head from the housing you should be able to run it as is unless there was an issue to begin with. What all has been replaced at this point?

[DMC81]

At the very least you need a dwell meter for this. Best case an air fuel meter. How far did you have the top apart? Did you pull everything off together? IE the metering housing with everything still attached? OR did you remove each individual component. If you have everything together right and did not pull the metering head from the housing you should be able to run it as is unless there was an issue to begin with. What all has been replaced at this point?


I took the FMU out as a whole i did not disassemble it at all, I just removed all the fuel lines vac lines, ect and set it aside.

[DMCMW Dave]

It is running rough still, Is this something that could be causing that? If so how do I go about adjusting it?

With only the paper clip instead of the RPM relay the lambda system (frequency valve) is not working.

[Delorean Industries]

I was assuming he followed standard protocol: fixed rpm relay issue and was diagnosing a rough running issue after. That is correct and would cause running issues if the lambda isn't already bypassed which wasn't mentioned. My mistake for assuming.

[DMC81]

I was assuming he followed standard protocol: fixed rpm relay issue and was diagnosing a rough running issue after. That is correct and would cause running issues if the lambda isn't already bypassed which wasn't mentioned. My mistake for assuming.

Prior to the RPM relay fail the car would fall on its face when you would try to accelorat to fast, you really had to ease into it to get it up to speed. From what I can tell the O2 sensor is long been removed from this car, I dont see it anywhere. Not even the wire for it.

[DSNW Toby]

Prior to the RPM relay fail the car would fall on its face when you would try to accelorat to fast, you really had to ease into it to get it up to speed. From what I can tell the O2 sensor is long been removed from this car, I dont see it anywhere. Not even the wire for it.

Here is some general guidance that will very rarely steer you wrong: In situations like this where some modifications or removals have been done, the first step is to get everything back to stock configuration. Then, you find out why somebody made the changes to work around some failure, fix that correctly, and then move on with the rest of the repair. We usually find that some fairly simple part failure has motivated somebody to perform all manner of whacky mods to work around the basic issue. The situation only gets worse from there, until nothing is working.

[WelmoedJ]

Since DMC81 said that using the paperclip instead of the RPM relay the engine runs the RPM relay obviously is a suspect.

DMC81: if you have another (known good) RPM relay, use that.
If that helps keeping the car going, proceed to checking the fuel/air mixture.
Should you have an original RPM relay and it shows defective, contact Bitsyncmaster for a modern replacement.

If the car runs, is the odour from the tail pipes smelling rich?
That should point you to the next thing to do.

Both Dave's and Toby's advices are very sound (of course :) , they're the specialists here).

[Bitsyncmaster]

Yes without using a double wire jumper on the RPM relay (or a good RPM relay), you lose the Lambda and heater on the WUR. If you're running open loop Lambda, you probably fixed the POs problem when you did the VOD so now you need to reset the mixture.

[DMC81]

At this time I do not have a backup RPM relay so I'll have to look into getting one. The PO had some home made exhaust set up on the car, I have removed the old exhaust and will be putting the original back on here soon. My question is where do I find the wire for the O2 sensor if he cut it off or removed it? Is it possible that the car will not accelerate normal because of the missing sensor?

[Bitsyncmaster]

At this time I do not have a backup RPM relay so I'll have to look into getting one. The PO had some home made exhaust set up on the car, I have removed the old exhaust and will be putting the original back on here soon. My question is where do I find the wire for the O2 sensor if he cut it off or removed it? Is it possible that the car will not accelerate normal because of the missing sensor?

You should see a connector (one pin) in the drivers side rear fender well.

[DMC81]

You should see a connector (one pin) in the drivers side rear fender well.


Thanks Dave, I'll take a peek and see what I find. Can you shoot me a PM with a price on the RPM relay when you get a free minute. Thank you.

[Delorean Industries]

Thanks Dave, I'll take a peek and see what I find. Can you shoot me a PM with a price on the RPM relay when you get a free minute. Thank you.

If the harness isn't showing its head through the fiberglass it is most likely bunched up behind the drivers seat in the ecu area. Hopefully it has not been cut off as it is shielded to the ecu.

[DMC81]

If the harness isn't showing its head through the fiberglass it is most likely bunched up behind the drivers seat in the ecu area. Hopefully it has not been cut off as it is shielded to the ecu.

Thanks Josh, I have yet to check it out, been really busy with city stuff. I do have another question though. I got the rmp / starting issue fixed but my acceleration problem is still there and very bad. If the car is parked I can rev the car up without hesitation for the most part but when I go to drive it I can not accelerate at a normal rate at all and some times I cant get it to accelerate at all. It just bogs down and wants to die out or idle. any ideas?

[David T]

Thanks Josh, I have yet to check it out, been really busy with city stuff. I do have another question though. I got the rmp / starting issue fixed but my acceleration problem is still there and very bad. If the car is parked I can rev the car up without hesitation for the most part but when I go to drive it I can not accelerate at a normal rate at all and some times I cant get it to accelerate at all. It just bogs down and wants to die out or idle. any ideas?

The first thing to check is if the Lambda system is functioning. It "adds" a little fuel to bring the A/F ratio close to ideal. If it is not working you are probably running too lean. You can also have vacuum leaks. Make sure the plug is in place over the mixture screw. You should hear the frequency valve on the R/H valve cover buzzing. If it isn't you need to figure out why.

[DMC81]

The first thing to check is if the Lambda system is functioning. It "adds" a little fuel to bring the A/F ratio close to ideal. If it is not working you are probably running too lean. You can also have vacuum leaks. Make sure the plug is in place over the mixture screw. You should hear the frequency valve on the R/H valve cover buzzing. If it isn't you need to figure out why.

Just thinking back and I don't recall the frequency valve making any noise. I'll check it out when I get off work. I know mine looks really, really bad though. Lost of corrosion all over it. What would be the best rout to go to replace it?

[David T]

Just thinking back and I don't recall the frequency valve making any noise. I'll check it out when I get off work. I know mine looks really, really bad though. Lost of corrosion all over it. What would be the best rout to go to replace it?

The valve itself rarely goes bad. Usually a bad connection somewhere or a relay. First thing to do is to remove and replace the plug on the valve a couple of times. The connections can oxidize and putting the plug on and pulling it off can clean the contacts up and get it running. If that doesn't do it you have to look "deeper". If it isn't buzzing the motor will have no power. it will start and run at idle but it can't make the car move very well.

[DMC81]

The valve itself rarely goes bad. Usually a bad connection somewhere or a relay. First thing to do is to remove and replace the plug on the valve a couple of times. The connections can oxidize and putting the plug on and pulling it off can clean the contacts up and get it running. If that doesn't do it you have to look "deeper". If it isn't buzzing the motor will have no power. it will start and run at idle but it can't make the car move very well.

Ok, I started the car up and I could here the FV buzzing so I let it run for about 5min then noticed the buzzing stopped. So I am going to assume the relay is bad. Sound right?

[DMCMW Dave]

Ok, I started the car up and I could here the FV buzzing so I let it run for about 5min then noticed the buzzing stopped. So I am going to assume the relay is bad. Sound right?

No. That means it is working and your CO is way out of adjustment.

[DMC81]

No. That means it is working and your CO is way out of adjustment.

I know I'm going to say duh when you tell me but. CO? I thought it was to buzz at all times?

[Bitsyncmaster]

I know I'm going to say duh when you tell me but. CO? I thought it was to buzz at all times?

"CO" is mixture adjustment. If the FV stops buzzing the mixture is to far off and it's trying to compenste but has run out of it's range of adjustment.

[DMC81]

"CO" is mixture adjustment. If the FV stops buzzing the mixture is to far off and it's trying to compenste but has run out of it's range of adjustment.

So next step would be to adjust the air and fuel mixture? Is there a good thread for doing so?

[Bitsyncmaster]

So next step would be to adjust the air and fuel mixture? Is there a good thread for doing so?

First, you do have the working RPM relay and an O2 sensor connected? Do you have a dwell meter?

[DMC81]

First, you do have the working RPM relay and an O2 sensor connected? Do you have a dwell meter?

I do have a good RPM relay but the 02 is not hooked up.

[DMC81]

22442

These are hanging by the driver side axle shaft....o2 wires?

[DeLorean03]

22442

These are hanging by the driver side axle shaft....o2 wires?

Possibly the otterstat wires. Look at your metal cooling pipe on the driver's side (while laying on the ground). You should see a sensor plugged into the pipe with two male spades protruding from it. That will be your otterstat. If there are no wires on the male spades, those two wires could be the ones that go on it. To know for sure, turn your key to where you hear the fuel pump prime. While the key is in that position, touch those two wires together. If you hear your cooling fans come on, those wires hook up to the otterstat.

[DMC81]

Possibly the otterstat wires. Look at your metal cooling pipe on the driver's side (while laying on the ground). You should see a sensor plugged into the pipe with two male spades protruding from it. That will be your otterstat. If there are no wires on the male spades, those two wires could be the ones that go on it. To know for sure, turn your key to where you hear the fuel pump prime. While the key is in that position, touch those two wires together. If you hear your cooling fans come on, those wires hook up to the otterstat.

Otterstat is hooked up so they dont go there.

[DMC81]

I think it is the REVERSE HARNESS 106116, I cant see the 02 wire yet. The 02 is a blue covered wire coming out of the box correct? Then through the fire wall?

[Bitsyncmaster]

I think it is the REVERSE HARNESS 106116, I cant see the 02 wire yet. The 02 is a blue covered wire coming out of the box correct? Then through the fire wall?

There are two blue wires in the drivers side rear compartment. One is the distributor pickup wire going to the ignition ECU. The other is a blue wire coming from the Lambda ECU and then goes to the O2 sensor through the wheel well.

[DMC81]

There are two blue wires in the drivers side rear compartment. One is the distributor pickup wire going to the ignition ECU. The other is a blue wire coming from the Lambda ECU and then goes to the O2 sensor through the wheel well.

I found both Dave, I will have to track down the other end tomorrow and see if it has been cut off or what. Can I fix my mixture problem without the 02 hooked up?

[Bitsyncmaster]

I found both Dave, I will have to track down the other end tomorrow and see if it has been cut off or what. Can I fix my mixture problem without the 02 hooked up?

You are running open loop without the O2. Yes you can adjust it but you will need an exhaust gas analyzer to set it.

[DMC81]

You are running open loop without the O2. Yes you can adjust it but you will need an exhaust gas analyzer to set it.

LOL, "This is heavy" Is there a thread on basic step to adjust the mixture screw?

[DeLorean03]

LOL, "This is heavy" Is there a thread on basic step to adjust the mixture screw?

If you are going to go open loop (I have for 7 years now), there is a hole in front of the fuel distributor. In that hole is a 3mm allen wrench screw. That is where you adjust it. Clockwise is richen - counter-clock to lean. It does NOT take very much to make a significant difference. I'd only turn it about 1/16 (like from 6 O'clock to 7 O'clock) and see if that changes the condition of the car's idle/running. Make these adjustments with a hot engine (cooling fans have turned on and off one time.

I would also add to this:only do this if EVERYTHING else is working right (minus the lambda system, since running "open loop" is in essence, running without the lambda system). This can be considered a band-aid to an overarching bigger problem. It is NOT a band-aid if you simply desire to run open loop.

[DMC81]

If you are going to go open loop (I have for 7 years now), there is a hole in front of the fuel distributor. In that hole is a 3mm allen wrench screw. That is where you adjust it. Clockwise is richen - counter-clock to lean. It does NOT take very much to make a significant difference. I'd only turn it about 1/16 (like from 6 O'clock to 7 O'clock) and see if that changes the condition of the car's idle/running. Make these adjustments with a hot engine (cooling fans have turned on and off one time.

I would also add to this:only do this if EVERYTHING else is working right (minus the lambda system, since running "open loop" is in essence, running without the lambda system). This can be considered a band-aid to an overarching bigger problem. It is NOT a band-aid if you simply desire to run open loop.

How do I remove the small silver cap ove the mixture screw that I see? Do I just pop it out with a small screw driver?

[DeLorean03]

How do I remove the small silver cap ove the mixture screw that I see? Do I just pop it out with a small screw driver?

Someone else will have to chime in on that one.

Personally, if there is a cap that has never been removed, I wouldn't mess with it. That says that the mixture has pretty much never been altered, and I'd work on getting the car running with the lambda system properly. Once that mixture is touched, it is very tricky to get in back to factory specs.

[DMC81]

Someone else will have to chime in on that one.

Personally, if there is a cap that has never been removed, I wouldn't mess with it. That says that the mixture has pretty much never been altered, and I'd work on getting the car running with the lambda system properly. Once that mixture is touched, it is very tricky to get in back to factory specs.

That just may be the right way to go but I just find it hard to believe that not having the 02 sensor hooked up would cause the problem I'm having.

[Bitsyncmaster]

Can you get a photo of that silver cap? If it is the original cap it needs to be drilled out. It may just be some PO found something to cap it.

[David T]

Can you get a photo of that silver cap? If it is the original cap it needs to be drilled out. It may just be some PO found something to cap it.

This is exactly the wrong way to do things. You adjust (if you NEED to) the mixture screw after you have EVERYTHING working as it should. If the Lambda system is not working then you need to fix that first. Get the O2 sensor hooked back up. You may have to replace it, that may be why it was disconnected, maybe not. If you run "Open Loop" you will have poor fuel economy and you will not get the motor to run well in all circumstances. Never mind that in most States you wouldn't pass emissions testing. In most cases that mixture screw is set just where it needs to be, without the right equipment you won't be able to adjust it any better than it already is set. Rarely, if ever, can you "adjust" a problem away. You need to find and FIX the problem and then you will see you do not have to touch that infamous mixture screw!

[DMC81]

This is exactly the wrong way to do things. You adjust (if you NEED to) the mixture screw after you have EVERYTHING working as it should. If the Lambda system is not working then you need to fix that first. Get the O2 sensor hooked back up. You may have to replace it, that may be why it was disconnected, maybe not. If you run "Open Loop" you will have poor fuel economy and you will not get the motor to run well in all circumstances. Never mind that in most States you wouldn't pass emissions testing. In most cases that mixture screw is set just where it needs to be, without the right equipment you won't be able to adjust it any better than it already is set. Rarely, if ever, can you "adjust" a problem away. You need to find and FIX the problem and then you will see you do not have to touch that infamous mixture screw!

When I got the car it had a cheap home built exhaust setup on it and no 02 sensor so I got a nice used OE exhaust system and I hope to have it on the car within a week or so and then maybe once I get the new 02 hooked up it will help. Can not having the 02 really cause that much of a problem on these cars tho?

[DeLorean03]

Can not having the 02 really cause that much of a problem on these cars tho?

Without getting into too long of an explanation, yes.

[DMC81]

Without getting into too long of an explanation, yes.

Thats a good enough answer for me. lol I'll get the exhaust back on with a new 02 sensor and I'll go from there. Thanks guys :rock_on:

[DMC81]

22505

Is this where my 02 sensor plugs into? This behind the left rear wheel, Thanks.

[Bitsyncmaster]

22505

is this where my 02 sensor plugs into? This behind the left rear wheel, thanks.

yes.

[DMC81]

yes.

Thank you Dave. :rock_on: