Car quit...advice needed

[jeff]

Hey guys, I obviously haven't posted much here or even or even on the "old" DMCtalk lately. Mainly because my D has been fantastic, driving tons....BUT (and I know you guys love these threads):wink:

On my way back from a camping trip this morning on the highway the car starts hesitating/missing. Cruising at 60 mph, then like someone flicked a switch, it's starts acting up. However I continue to maintain my speeds for a another 10 miles or so. There is something wrong...but if I had a passenger they probably wouldn't have even noticed.

I take the off ramp and when I start slowing down, the car kinda sputters and quits. Gauges are all fine, I checked the oil, it's fine. I try to start it, turns over, but doesn't fire. So sitting in the car I start making some phone calls for a tow truck. I'm sitting in the car for maybe 10 mins max. I try to start it, it fires up. NO symptoms, and I drive home a few miles.:confused0:

Any ideas?

I have a 1/8 of a tank of gas so I'm thinking the "hot" gas issue. But it's 60 degrees and pouring rain. So it's not hot out at all. I've old had this issue once before in a different D but it was hot outside and I was driving in the city. But symptoms were similiar.

Thanks in advance.

[Bitsyncmaster]

Usually the hot gas issue will cause the fuel pump to get louder. It may be your RPM relay. You should make up a jumper and keep it in the car for when it does it again. Then if the jumper gets you home no problems you probably know the issue is the relay.

You need a 3 pin jumper to drive with it jumpered. If you only use the two pin jumper your lambda system is not working.

[jeff]

Ahhh yeah you're right...the loud buzzing sound, I remember now.

Would the RPM relay cause those symptoms? Is the solid state "better" relay still around?

[David T]

I would suspect a problem in the fuel pumping system. Either an electrical problem or something going on inside the tank. Next time this happens try to figure out of the pump is running. If not then figure out why by jumping things till you can get it to run. Very common for the RPM relay to fail intermittently. Easy to jump out temporarily to test. Can also be a problem with the inertia switch. You should have had the recall done if applicable and the inertia switch should have a splotch of white paint on it. The wiring to the pump under the cover boot can get all corroded if the boot leaks so check that and finally the plugs in the wiring harness up inside the W/W bucket get corroded and fail to make good electrical contact. Do not just assume a part is bad and start "shotgunning" for it by randomly replacing parts. Can take a lot of time and money that way and you will wind up with a pile of a lot of good parts laying on the shelf!
David Teitelbaum

[Bitsyncmaster]

Ahhh yeah you're right...the loud buzzing sound, I remember now.

Would the RPM relay cause those symptoms? Is the solid state "better" relay still around?

It all depends but mostly an intermittent relay will kill the engine and then be fine after it cools down until the next time.

[jeff]

Usually the hot gas issue will cause the fuel pump to get louder. It may be your RPM relay. You should make up a jumper and keep it in the car for when it does it again. Then if the jumper gets you home no problems you probably know the issue is the relay.

You need a 3 pin jumper to drive with it jumpered. If you only use the two pin jumper your lambda system is not working.

Sorry Dave, after a quick search I realized that it is you that sells the solid state relay.


I would suspect a problem in the fuel pumping system. Either an electrical problem or something going on inside the tank. Next time this happens try to figure out of the pump is running. If not then figure out why by jumping things till you can get it to run. Very common for the RPM relay to fail intermittently. Easy to jump out temporarily to test. Can also be a problem with the inertia switch. You should have had the recall done if applicable and the inertia switch should have a splotch of white paint on it. The wiring to the pump under the cover boot can get all corroded if the boot leaks so check that and finally the plugs in the wiring harness up inside the W/W bucket get corroded and fail to make good electrical contact. Do not just assume a part is bad and start "shotgunning" for it by randomly replacing parts. Can take a lot of time and money that way and you will wind up with a pile of a lot of good parts laying on the shelf!
David Teitelbaum

Great advice.

Daves :smile: Do you guys have a quick pic of the jumper that I should use?

[TTait]

please excuse any typos in this reply I am dictating instead of typing.

I'm guessing that your right and that the fuel pump either overheated or became clogged. Debris can be sucked up against the filter screen and clogging the fuel pump causing it to overheat

or it may have just overheated because of high temperature.

if you have already filled the tank again then I would say just drive it and carefully watch what happens


learn to listen for the sound of the fuel pump priming itself for the first second after you turn the key to run this is important when diagnosing problems in the future turn the key to run but not start and you will hear the pump hum for almost 1 second.
in the future if you do not hear this then your fuel pump is either overheated or your rpm relay is defective.


when you do not hear the pump prime properly then either your fuel pump is overheated or the rpm relay is bad

my guess is the fuel pump overheated however, I do because of heat or because the filter screen got clogged or both

it is also possible that the fuel pick up lines between the filter screen and pump collapsed.

the tank is low on gas now would be a good time to check and make sure everything looks good. Empty the trunk and remove the spare
Tire.

Remove about 12 philips head screws and carefully pry out the fuel pump access cover

Clean and inspect everything under the cover

Check for any gas leaks there should not be any

At any point where you see something which is obviously wrong stop and take pictures to post here

Remove the access cover over the fuel level sending unit clean and inspect everything there

Remove large locking nut for the fuel level sensor and carefully lift it out. Look into the tank for debris corrosion or water. Make
Sure
There are no kinks in the fuel pickup line coming from the bottom of the pump.

Make sure the feed and return lines from the top of the pump are clean and then loosen the giant hose clamp around the pump assembly. Slide the top cover up along the two hoses to access the top of the pump. It should be clean and pristine with no gas in this area. If not take photos.

By the way its a good time to mention just how unhealthy smoking is...

Now lift the pump out as far as you can watching the bottom hose.

Look for damage and debris. There may me a spring inserted inside your lower hose so it cant collapse. Give it a squeeze.

I happen to prefer Herveys baffle and pickup but both oem and herveys are both fine. Ignore alarmists on either side.

Let us know what you find.

In the meantime:

Can you hear the pump prime?

When.Was the fuel pump last serviced

Is there a spring in your pick up line?

Was it really hot when the car failed?

How old is the rpm relay?


Get AAA.

[Bitsyncmaster]

Sorry Dave, after a quick search I realized that it is you that sells the solid state relay.



Great advice.

Daves :smile: Do you guys have a quick pic of the jumper that I should use?

Jumper is just 16 AWG wire and three crimp pins. This is the one I carry in my car.

[jeff]

Car has over 80000 miles...I drive it tons. TTait, it's 60 degrees here and pouring rain...I don't think it was an overheated pump. After Dave refreshed my memory (buzzing and loud) when it's hot, I'm convinced. Definately possible something could have gotten in the tank, collapsed pickup. But like I say the amount I drive it, stored inside etc.

I just drove the car 10 minutes ago, everything is fine. Tough to diagnose a problem when it's intermittent. I did pull the RPM relay, I don't know how old it is?? says made in Germany with a bunch of numbers and what looks like a date 1980, LOL!!! Black with blue in the bottom.

I know David T said don't start spending money on stuff when you don't know. But, assuming that my RPM relay is old, I think it's time for an upgrade. Dave M PM sent.

I'll keep you guys posted. I'll make a jumper keep it handy and if or when it happens again, I'll use the jumper and see if it makes a difference.

[DeLorean03]

Black with blue in the bottom.

I know David T said don't start spending money on stuff when you don't know. But, assuming that my RPM relay is old, I think it's time for an upgrade. Dave M PM sent.


Black and blue? Dude, that is a 30 year old RPM relay....definitely get rid of it. That is probably your issue. Typically with "missing and sputtering" happening all of a sudden like that = something electrical going awry. New RPM relay and you should be good!

[DeLorean03]

... the W/W bucket...

I've been in the community for 8 years, and totally am brainfarting as to what part of the car you're referring to? Can you please clarify this, as my curiosity has been peaked (: ?

[DMCMW Dave]

I've been in the community for 8 years, and totally am brainfarting as to what part of the car you're referring to? Can you please clarify this, as my curiosity has been peaked (: ?

The black "bucket" around the windshield washer reservoir. It tends to get plugged up at the bottom and fill up with water. If you have it off for any reason drill out drain holes much larger. 3/8" or so. DO NOT DO THIS IN PLACE or you'll drill into the tank too.

[TTait]

Yeah, if you have an original relay replace it - in fact replace all of them.

Still though because you are flirting with other possibilities I again suggest looking at AAA premier service - 100 miles of towing (flatbed included) is great to have in your back pocket. DMCCA is about 75 miles away from me now - and traffic an be a PAIN on some days. I'll admit that I have called AAA to tow the vehicle down there for me free just because I have wanted to get misc. work done and didn't feel like driving it and hasseling with taking the train home.

[sdg3205]

Dave/Bitsyncmaster's solid state RPM relay is worth the money.

[A Van]

Might be worth just checking spade connections at the ignition coil and ballast resistors.

[Chris 16409]

Jumper is just 16 AWG wire and three crimp pins. This is the one I carry in my car.

Hey Dave, what terminals do you use for the three wire jumper. Hervey has the two jumper spots shown. Which one is the third?

[Bitsyncmaster]

Hey Dave, what terminals do you use for the the three jumper. Hervey has the two jumper spots shown. Which one is the third?


I've committed this to memory. Just remember the two heavy gauge wires power the pump and the double wire also needs power (that's the lambda).

Brown to white/purple to double yellow/red