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Help...going out of town... intermittent rough idle and stalling

2101 Views 4 Replies 3 Participants Last post by  Aerosurfer
92 400SE has an intermittent rough idle and stalling problems.

It usually occurs shortly after reaching operating temperature. It may suddenly die at idle, be hard to restart, and then miss under load at lower RPM. Or it will start missing under load, refuse to idle, etc. These episodes may go on for half an hour and persist if the car is shut off and restarted. Then it will clear up and run well for some time.

I dont' get a check engine light. I've checked fuses in the Control Module. (NO OVP Module in 92 400se)

I've done a search on possible solutions.

I've called the dealer to see if they will read the engine scan codes but they are booked up due to the holiday weekend.

I've changed the distributor caps, rotors, wiring harness, sparkplugs. I'll be changing the following parts today.

Fuel Pump Relay
Fuel pump
Fuel Filter
Fuel Pressure Regulator
Ignition Coil
Air Temp Sensor
Oxygen Sensor

I called the local Autozone and they dont read engine scan codes on Mercedes. Any non MB that can read scan codes?

Thanks in advance for any suggestions.

Russell
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· Registered
1982 Mercedes-Benz 380sl
Joined
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30 Posts
92 400SE has an intermittent rough idle and stalling problems.

It usually occurs shortly after reaching operating temperature. It may suddenly die at idle, be hard to restart, and then miss under load at lower RPM. Or it will start missing under load, refuse to idle, etc. These episodes may go on for half an hour and persist if the car is shut off and restarted. Then it will clear up and run well for some time.

I dont' get a check engine light. I've checked fuses in the Control Module. (NO OVP Module in 92 400se)

I've done a search on possible solutions.

I've called the dealer to see if they will read the engine scan codes but they are booked up due to the holiday weekend.

I've changed the distributor caps, rotors, wiring harness, sparkplugs. I'll be changing the following parts today.

Fuel Pump Relay
Fuel pump
Fuel Filter
Fuel Pressure Regulator
Ignition Coil
Air Temp Sensor
Oxygen Sensor

I called the local Autozone and they dont read engine scan codes on Mercedes. Any non MB that can read scan codes?

Thanks in advance for any suggestions.

Russell
Hey Russell, I a similar issue, did you ever figure it out?
 

· Registered
99 CL500.
Joined
·
403 Posts
Hey Russell, I a similar issue, did you ever figure it out?
Its a 19 year old post and he hasnt been on the site since 2014... you may not get a great answer from him...

Whats your car symptoms, specs and what have you done so far
 

· Registered
1982 Mercedes-Benz 380sl
Joined
·
30 Posts
Its a 19 year old post and he hasnt been on the site since 2014... you may not get a great answer from him...

Whats your car symptoms, specs and what have you done so far
I have a 1982 380sl.
I am having troubles with a rough idle once the car has warmed up. I don’t have this issue when it’s cold and it starts easily when cold too but turns over a little once warmer. The fuel seems to be rich. I have been chasing this problem changing O2 sensor, ICU, Fuel pump and filter, Spark plugs, etc.. but still have no success. I will soon be testing for vacuum leaks and checking the fuel pressure. I am also considering adjusting the 3mm on the fuel distributor that adjusts CO2, but am hesitant and wondering why many say this is a bad idea. Does it help with rough idle or just high/low idle? My engine bay seems to be wet with an oil leak somewhere, could this have something to do with it? Should my crankcase breather hose have oil caked up in it? I have also heard that the timing chain alignment may have something to do with it.
 

· Registered
99 CL500.
Joined
·
403 Posts
You may get a better answer in the R107 forum... much more relevant to the components you have

This is for W140s.
 
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