SL/R129: 1992 SL500 dies while driving
Thread Starter
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1992 SL500 dies while driving
Hello everyone,
I own a 92 SL500. Recently got fuel distributor and bosch caps replaced. Drove perfectly for a couple of days, then one time the engine died while driving. Starter cranks strong rpm goes up for a sec then engine dies and refuses to start again. Replaced battery, started like new, drove around and again it died. MAS module tested and works fine, alternator charge is fine. New fuel pumps , bosch accumolator, plugs..
any body had experienced the the same symptoms? Any ideas?
Thanks!
I own a 92 SL500. Recently got fuel distributor and bosch caps replaced. Drove perfectly for a couple of days, then one time the engine died while driving. Starter cranks strong rpm goes up for a sec then engine dies and refuses to start again. Replaced battery, started like new, drove around and again it died. MAS module tested and works fine, alternator charge is fine. New fuel pumps , bosch accumolator, plugs..
any body had experienced the the same symptoms? Any ideas?
Thanks!
MBWorld Fanatic!
Joined: Mar 2016
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From: SF Bay Area, CA
190E 2.6L 1989, 190E 2.6L 1988, BMW 535dXdrive 2014, BMW 428i 2015
Does it struggle and die or just shut down. If it is fueling issue it will "struggle". If it just shuts down that is generally the lack of air or ignition that causes it.
So idle control or ignition circuits.
So you need to first make a call on that before diving in.
So idle control or ignition circuits.
So you need to first make a call on that before diving in.
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No struggle just shuts down. Recently i replaced distributor and idle hoses, could be the reason. Will check. Thank you!
MBWorld Fanatic!
Joined: Mar 2016
Posts: 1,369
Likes: 195
From: SF Bay Area, CA
190E 2.6L 1989, 190E 2.6L 1988, BMW 535dXdrive 2014, BMW 428i 2015
First question I would ask is has your car been garaged for the past 32 years? And is it in a humid climate?
I have 2 W201's. 88 and 89. The 89 daily used for 36 years and garaged in dry climate. Has no electrical gremlins whatsoever.
The new acquisition 88 with less miles lived in Portland and SF all its life and probably not garaged, I have cleaned out a lot of connectors for this one.
Just fixed the auto antenna connector corrosion with de-oxit. I also cleaned out the ECU connector as it was throwing CEL once is a while. One does not see the oxidation but it is there.
So it could be simple corrosion/oxidation of random stuff.
Also do not overlook the possibility of a an old OVP just cutting off randomly. I have had that in the '89. After months of chasing an intermittent shut-off while changing gears (manual tran) it turned out to be the OVP. I could write a chapter on why a car dies on an intermittent OVP. Later maybe....
If you have not replaced the OVP already, pull it out and check the date code on it and if over 10 years old just replace it with an MB one and keep the old one for later use.
MB and KAE are fine, all the rest are suspicious. URO ones are junk.
- Cheers!
I have 2 W201's. 88 and 89. The 89 daily used for 36 years and garaged in dry climate. Has no electrical gremlins whatsoever.
The new acquisition 88 with less miles lived in Portland and SF all its life and probably not garaged, I have cleaned out a lot of connectors for this one.
Just fixed the auto antenna connector corrosion with de-oxit. I also cleaned out the ECU connector as it was throwing CEL once is a while. One does not see the oxidation but it is there.
So it could be simple corrosion/oxidation of random stuff.
Also do not overlook the possibility of a an old OVP just cutting off randomly. I have had that in the '89. After months of chasing an intermittent shut-off while changing gears (manual tran) it turned out to be the OVP. I could write a chapter on why a car dies on an intermittent OVP. Later maybe....
If you have not replaced the OVP already, pull it out and check the date code on it and if over 10 years old just replace it with an MB one and keep the old one for later use.
MB and KAE are fine, all the rest are suspicious. URO ones are junk.
- Cheers!
Junior Member
Joined: Nov 2016
Posts: 43
Likes: 8
From: San Francisco Bay Area, CA
This may be a bit silly to suggest but are you 100% sure that ALL the grounds on the car are secure and not loose? On my E39 BMW my car would randomly shut off when driving sometimes and it was all due to a loose ground connection. Could a loose ground where the ignition coils are cause this?
Thread Starter
Newbie
Joined: Dec 2024
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First question I would ask is has your car been garaged for the past 32 years? And is it in a humid climate?
I have 2 W201's. 88 and 89. The 89 daily used for 36 years and garaged in dry climate. Has no electrical gremlins whatsoever.
The new acquisition 88 with less miles lived in Portland and SF all its life and probably not garaged, I have cleaned out a lot of connectors for this one.
Just fixed the auto antenna connector corrosion with de-oxit. I also cleaned out the ECU connector as it was throwing CEL once is a while. One does not see the oxidation but it is there.
So it could be simple corrosion/oxidation of random stuff.
Also do not overlook the possibility of a an old OVP just cutting off randomly. I have had that in the '89. After months of chasing an intermittent shut-off while changing gears (manual tran) it turned out to be the OVP. I could write a chapter on why a car dies on an intermittent OVP. Later maybe....
If you have not replaced the OVP already, pull it out and check the date code on it and if over 10 years old just replace it with an MB one and keep the old one for later use.
MB and KAE are fine, all the rest are suspicious. URO ones are junk.
- Cheers!
I have 2 W201's. 88 and 89. The 89 daily used for 36 years and garaged in dry climate. Has no electrical gremlins whatsoever.
The new acquisition 88 with less miles lived in Portland and SF all its life and probably not garaged, I have cleaned out a lot of connectors for this one.
Just fixed the auto antenna connector corrosion with de-oxit. I also cleaned out the ECU connector as it was throwing CEL once is a while. One does not see the oxidation but it is there.
So it could be simple corrosion/oxidation of random stuff.
Also do not overlook the possibility of a an old OVP just cutting off randomly. I have had that in the '89. After months of chasing an intermittent shut-off while changing gears (manual tran) it turned out to be the OVP. I could write a chapter on why a car dies on an intermittent OVP. Later maybe....
If you have not replaced the OVP already, pull it out and check the date code on it and if over 10 years old just replace it with an MB one and keep the old one for later use.
MB and KAE are fine, all the rest are suspicious. URO ones are junk.
- Cheers!
we finally located the problem. It was the EHA valve o ring! Changed it..car starts and drives perfectly.
Cheers
Last edited by EKR129; Dec 27, 2024 at 04:22 AM.
MBWorld Fanatic!
Joined: Mar 2016
Posts: 1,369
Likes: 195
From: SF Bay Area, CA
190E 2.6L 1989, 190E 2.6L 1988, BMW 535dXdrive 2014, BMW 428i 2015
Not your typical failure mode I must say. Normally they start leaking to the outside before the o-ring(s) go. Although I have never opened the adjustment mechanism like that.
I assume you put it back together exactly how it came out? Or maybe you readjusted it? Would it not leak fuel if the o-ring was bad? Just asking questions as I do not have the answers.
I assume you put it back together exactly how it came out? Or maybe you readjusted it? Would it not leak fuel if the o-ring was bad? Just asking questions as I do not have the answers.
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Thread Starter
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dolucasi.. certainly not the typical failure...i put it back exactly how it came out.
there were no leaks, two cylinders were not getting fuel the way they should one was
getting too little and one too much. it did smell rich.
the question is, will this be the end of the random engine shut down or it only solved the "no start" issue... I guess time will tell..
so far the car is running smoothly
there were no leaks, two cylinders were not getting fuel the way they should one was
getting too little and one too much. it did smell rich.
the question is, will this be the end of the random engine shut down or it only solved the "no start" issue... I guess time will tell..
so far the car is running smoothly
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MBWorld Fanatic!
Joined: Mar 2016
Posts: 1,369
Likes: 195
From: SF Bay Area, CA
190E 2.6L 1989, 190E 2.6L 1988, BMW 535dXdrive 2014, BMW 428i 2015
dolucasi.. certainly not the typical failure...i put it back exactly how it came out.
there were no leaks, two cylinders were not getting fuel the way they should one was
getting too little and one too much. it did smell rich.
the question is, will this be the end of the random engine shut down or it only solved the "no start" issue... I guess time will tell..
so far the car is running smoothly
there were no leaks, two cylinders were not getting fuel the way they should one was
getting too little and one too much. it did smell rich.
the question is, will this be the end of the random engine shut down or it only solved the "no start" issue... I guess time will tell..
so far the car is running smoothly
Hopefully the car was not run like that for long as that will ruin piston rings because the super rich cylinders get washed out and starved for much needed lubrication of the oil.
You probably have underlying FD issues too and should make sure the fueling is good and even under all engine driving conditions.
I would first check the Duty cycle at idle versus 2500rpm and make sure it does not vary too much (less than 10%).
And remember that the EHA current actually varies even more under load conditions in which case there is more demand for fuel if there is a fuel delivery issue from the injectors.
But again the cause of the random shutdown I suspect is something different.
