Waking the car up from a nap

[OverlandMan]

So if anyone has been following for the past year and a half, I've been slowly rebuilding and cleaning the entire fuel system in 5482. I believe I have literally touched every component in this system.


Cleaned the fuel tank
New fuel pump, boot, baffle screen, & rubber lines
Fresh gas
New DPI fuel line kit
Cleaned injectors & flow tested
New injector rubber seals
New copper crush washers
New fuel filter
New fuel accumulator
Fixed stuck plunger in fuel distributor
New banjo bolts
New injector clips


I also replaced these components in the engine compartment:

Spark plugs
Ignition wires
Distributor cap & rotor


Up until Saturday, the car had not run since September 2013. A couple weeks back, I tried to crank it up but couldn't get it to run or even try. Turns out my old fuel pump died (thud sound when powering). I replaced that and jumped the RPM relay to prime the system for a few seconds. Now I can get it to run (It's alive!) for a few seconds and then it immediately dies. I can repeat the process for what seems indefinitely. The car will run for a few seconds, then die.

In pondering this a bit, my initial thoughts are maybe the RPM relay is failing and not keeping the fuel pump running? I should be able to jump it and test that theory. If that's not it, another thought I had was maybe the new DMCH intake hose in the tank is collapsing? I recall hearing members using a screen door spring to keep that line from collapsing.

I thought I'd see what you guys thought in addition to my two initial theories. It seems like a fuel delivery issue since I can get it to run for a few seconds every time I try to start it up. I would think oxygen and spark can be eliminated here. What say you guys?

[David T]

So if anyone has been following for the past year and a half, I've been slowly rebuilding and cleaning the entire fuel system in 5482. I believe I have literally touched every component in this system.


Cleaned the fuel tank
New fuel pump, boot, baffle screen, & rubber lines
Fresh gas
New DPI fuel line kit
Cleaned injectors & flow tested
New injector rubber seals
New copper crush washers
New fuel filter
New fuel accumulator
Fixed stuck plunger in fuel distributor
New banjo bolts
New injector clips


I also replaced these components in the engine compartment:

Spark plugs
Ignition wires
Distributor cap & rotor


Up until Saturday, the car had not run since September 2013. A couple weeks back, I tried to crank it up but couldn't get it to run or even try. Turns out my old fuel pump died (thud sound when powering). I replaced that and jumped the RPM relay to prime the system for a few seconds. Now I can get it to run (It's alive!) for a few seconds and then it immediately dies. I can repeat the process for what seems indefinitely. The car will run for a few seconds, then die.

In pondering this a bit, my initial thoughts are maybe the RPM relay is failing and not keeping the fuel pump running? I should be able to jump it and test that theory. If that's not it, another thought I had was maybe the new DMCH intake hose in the tank is collapsing? I recall hearing members using a screen door spring to keep that line from collapsing.

I thought I'd see what you guys thought in addition to my two initial theories. It seems like a fuel delivery issue since I can get it to run for a few seconds every time I try to start it up. I would think oxygen and spark can be eliminated here. What say you guys?

Sounds like it is running on the cold start valve and when it shuts off the motor stops. Try holding the air sensor plate down a little when it starts to see if you can keep it running. You might need a slight adjustment to the mixture screw. To see if the RPM relay is the problem jump it out temporarily.

[OverlandMan]

Sounds like it is running on the cold start valve and when it shuts off the motor stops. Try holding the air sensor plate down a little when it starts to see if you can keep it running. You might need a slight adjustment to the mixture screw. To see if the RPM relay is the problem jump it out temporarily.

That's something I hadn't thought of and would make sense. I'll have to enlist a helper because I don't have enough time between the key turn and the motor quitting to get out and to the back of the car to accomplish. I test this out ASAP and post the results.

If it turns out I do have to hold the mixture plate down to keep it running, you're saying it would be a mixture screw adjustment in order to correct? Any further details on that would be great.

When I was flow testing the injectors, I had to press down on the plate in order to get them to spray, which is normal operation. How does this (the fuel dist, air plate, etc.) work at startup under normal conditions?

[DMCMW Dave]

That's something I hadn't thought of and would make sense. I'll have to enlist a helper because I don't have enough time between the key turn and the motor quitting to get out and to the back of the car to accomplish. I test this out ASAP and post the results.

If it turns out I do have to hold the mixture plate down to keep it running, you're saying it would be a mixture screw adjustment in order to correct? Any further details on that would be great.

When I was flow testing the injectors, I had to press down on the plate in order to get them to spray, which is normal operation. How does this (the fuel dist, air plate, etc.) work at startup under normal conditions?

You should set the CO so that nothing comes out of the injectors with the plate at rest, but they start flowing at the tiniest pressure. That should be within a half turn of where it should be.

[OverlandMan]

You should set the CO so that nothing comes out of the injectors with the plate at rest, but they start flowing at the tiniest pressure. That should be within a half turn of where it should be.

I think that's how it's set now. It ran well back in the day and I didn't make any changes.

So if Dave T's theory is that the cold start is starting the engine but then it dies... what would be causing that (assuming pressing down on the air plate does keep it running)?

[SS Spoiler]

Ballest resistors?

[David T]

Ballest resistors?

That is also a strong possibility, since the engine quits as soon as you stop cranking. Actually it would be a connection on the second part (the bypassed part of the ballast resistor during starting) that would be the problem. I suggested fuel first as the more likely culprit but it could be electrical. That's why I asked him to try holding the sensor plate. If that makes ANY difference then it means it is a fuel problem. Although DMCW Dave is right about getting the adjustment close, that assumes the frequency valve is working too. If it isn't then you would be running very lean and pushing on the air sensor plate should be enough to keep it running. That would tell us there is some kind of a problem with the fuel system. Since it is a very easy thing to do (it requires NO tools or extensive knowledge) I suggested it (it does require a helper!).

[DMCMW Dave]

Ballest resistors?

Good call.

Usually this symptom is plugged injectors or fuel distributor.

The key is if you can make it run by pressing the plate, if that doesn't work either check the electrics as Paul mentioned.

[OverlandMan]

Good call.

Usually this symptom is plugged injectors or fuel distributor.

The key is if you can make it run by pressing the plate, if that doesn't work either check the electrics as Paul mentioned.

I performed 2 tests tonight.


Jumped the RPM relay and tried starting
Pushed down on the air plate about 1/4 down and tried starting



Niether problem seemed to have any affect. The car tries to run for a second or two at most and that's it. I also went through and checked all my fuses, which were fine.

Is there a test I can do on the ballast resistor to check to see if it's bad? I'm guessing I should be able to take an Ohm reading or something with a multi-meter.

Worth mentioning, when I first got it running on Saturday, it ran for 15-20 seconds before it died, then just started doing the 1-3 run then die symptom. This makes me think the injectors and fuel dist are probably ok?

[Jonathan]

Is there a test I can do on the ballast resistor to check to see if it's bad? I'm guessing I should be able to take an Ohm reading or something with a multi-meter.

Double check the connections are where they should be on the ballast resistor and the ignition coil under the bulkhead cover. Not underestimating your abilities, Jeff, just thinking of an oversight I made not long ago. I got checking connections and cleaning up the area and flat out left one of the ignition coil wires unplugged initially. Might be as simple as one of the connections isn't right. Post a pic or two of those two areas if you want someone else to look it over for you online.

[OverlandMan]

Double check the connections are where they should be on the ballast resistor and the ignition coil under the bulkhead cover. Not underestimating your abilities, Jeff, just thinking of an oversight I made not long ago. I got checking connections and cleaning up the area and flat out left one of the ignition coil wires unplugged initially. Might be as simple as one of the connections isn't right. Post a pic or two of those two areas if you want someone else to look it over for you online.

Fair enough. Here's a couple of pics of both area. Keep in mind, the only thing I disconnected and reconnected was the ignition coil. I have not touched the ballast resistor. I was pretty careful to make sure I reconnected the coil the same way I disconnected but there's always a possibility of screwing-up.

33778 33779

[DMC5180]

Did you wiggle the wire terminals on the ballast resistor? Pull them off and reconnect so they make a fresh scratch connection.

[Jonathan]

Nothing in those pics jumps out at me Jeff. One thing possibly could be the centre wire connection into the ignition coil isn't clipped down all the way. Not likely perhaps, but I don't see anything else.

[David T]

Nothing in those pics jumps out at me Jeff. One thing possibly could be the centre wire connection into the ignition coil isn't clipped down all the way. Not likely perhaps, but I don't see anything else.

Another quick way to see if it is fuel or ignition is to try squirting a little bit of Ether in and if that keeps it running, even a little bit longer, it tells you it is a fuel problem. For wiring diaphragms on the ignition circuit check out M:18:01, :02, :03 and :04 in the Workshop Manual. The place to start would be to make sure there is battery voltage on the white wire at the ballast resistor when the ignition key is on. M:18:04

[OverlandMan]

Talked to Dave @ DMCMW on the phone Tuesday evening. He recommended bypassing the ballast resistor (temporarily for testing purposes only) and jumping 12V straight from the (+) jump terminal to the (+) side of the coil, which I did. This didn't seem to change anything. He also mentioned reading through the resistor with a meter. As luck would have it, my 15 year old Blue-Point multi-meter died on me so I'm in the process of replacing that. No reading yet but that's where I am with it.

I did notice a fairly crispy looking white wire on the opposite side of the coil. I'll see about fixing that this weekend. That may be yielding a poor connection and causing some trouble. I haven't thoroughly investigated the connections on the ballast resistor yet but certainly will as well at the same time and correct as necessary.

I've been traveling the past couple of days but should have some time to work on it this weekend.

BTW - the folks @ DMCMW are fantastic!

[OverlandMan]

Alright, so here's where I am currently.

I cleaned all the electrical terminal connections on the coil and ballast resistor. Some of them were pretty cruddy looking. This didn't seem to change anything. I then decided to push the air plate down at least 3/4 of the travel and try again. This seemed to do the trick as a few more tries starting and it finally would run without dying.

Success! Kinda... now my problem is a bad miss and generally running like crap. I'm going to try and post a video on this thread later today or tomorrow. I'm thinking another flow test is probably in order to make sure I don't have a stuck injector or two. The spark plugs and wires were all replaced within the last 12 months and the connections there all seem fine.

I'm thinking the only other thing would be the fuel distributor. I did have a stuck plunger a couple of months back.

[David T]

Alright, so here's where I am currently.

I cleaned all the electrical terminal connections on the coil and ballast resistor. Some of them were pretty cruddy looking. This didn't seem to change anything. I then decided to push the air plate down at least 3/4 of the travel and try again. This seemed to do the trick as a few more tries starting and it finally would run without dying.

Success! Kinda... now my problem is a bad miss and generally running like crap. I'm going to try and post a video on this thread later today or tomorrow. I'm thinking another flow test is probably in order to make sure I don't have a stuck injector or two. The spark plugs and wires were all replaced within the last 12 months and the connections there all seem fine.

I'm thinking the only other thing would be the fuel distributor. I did have a stuck plunger a couple of months back.

Yes, the next step would be to check that all of the injectors are passing the same volume of fuel and each has a proper spray pattern. If you had a stuck plunger you probably should have the injectors cleaned and tested.

[OverlandMan]

Yes, the next step would be to check that all of the injectors are passing the same volume of fuel and each has a proper spray pattern. If you had a stuck plunger you probably should have the injectors cleaned and tested.

I did a flow test a while back but that was before I cleaned the tank and replaced all the tank components (several months). A couple of the injectors weren't spraying the same as the other 4 (less volume). I soaked them in Berryman's for several days and blew compressed air through them before re-testing and re-installing.

Seems like I recall hearing from one or more vendors back when that you can't really clean injectors. If they were cheaper, I'd just replace them all and be done with it.

http://dmctx.blogspot.com/2015/04/engine-running-headlight-switch-fix.html