380SE dies when car is idling or coming to a stop when the a/c is on. - PeachParts Mercedes-Benz Forum

duckster · #1 09-08-2002, 03:39 PM

I have a 1985 380 SE that is having a few struggles right now. Please help. If the car is idling and I turn the a/c on then the car dies. Also, when coming to a stop or slowing down when the a/c is on, the car will die.

On a few occasions, it has died while slowing down when the a/c is not on.

I bought the car about 6 months ago and from previous receipts I can see that a mechanic told the previous owner that the compression needs to be evened out and that there is a 40psi variation. HELP!!!!! What does this mean and is it my problem.

please help soon,
Trena

P.s. I have a broken spark plug wire also

Holson Adi · #2 09-08-2002, 08:19 PM

Have you done the basic stuff?

Air Filter, Fuel Filter(s), Spark Plugs (make sure you use the correct type), Distributor Cap/Rotor/Wires?

or maybe the idle is just set way too low?

What is the idle speed now?

Welcome to Mercedesshop btw

duckster · #3 09-09-2002, 04:39 PM

Thanks so much for replying.

I was about to order new wires and plugs today.
Should I order a new distributer cap and rotor and do everthing at once?

I am not sure what my idle speed is. As you can tell, I am new to the world of working on Mercedes. I have a 1985 380SE and a 1980 300SD. I am absolutely in love with Mercedes but will be seeking much guidance in the world of mechanics.

Trena

Holson Adi · #4 09-10-2002, 02:13 AM

I'm no mechanic so don't take my suggestions for granted..
I had a stalling problem with my friend's Camry the other day..
Here are what I did:

1. Techron Concentrate (Try this stuff..) it's bout $5 from Autozone and dump it in the tank when it's almost empty to run it at high concentration.

2. Spark Plugs (cheap Bosch Supers... for the Camry hehehe) - make sure you get the right plugs.. I have heard bad things about the Platinum Plugs.. but you could always give them a shot. You could also try the expensive Denso Iridiums .

3. Fuel Filter

Either the first or the second fixed the problem.. the third was something we did because we had nothing better to do.. and gasoline stinks.. I prefer diesel smell heheh less strong..

Try the spark plugs, fuel filters, air filter, and techron first...

BTW what is the idle speed?

Later,

engatwork · #5 09-10-2002, 06:51 AM

That broken spark plug wire is not helping the idle issue.

joe p · #6 09-10-2002, 07:56 AM

Make sure the secondary ignition is solid.
(wires, plugs etc...) Then remove and clean the ISC valve, little tube looking guy on top of the intake, clean with some decent carb cleaner. Put you thumb over one hole, fill it with cleaner, plug the other hole with you other thumb and shake. Do this untill the cleaner comes out fairly clear. Also clean the sensor plate, just blast it and be prepared for a hard start.

If it persists, check the lambda duty cycle, it should be about 50% fully warmed up, pin number 3 in the round connector on the l/h fenderwell, set your meter to duty and ground the other lead. 3mm allen in the a/f sensor, clockwise to richen.

Also check for vacum leaks if lean, this will cause the idle control to fail to "catch" the engine as its returning to idle.

Joe

Mervyn · #7 09-12-2002, 12:24 PM

Ignition Control Module - I've exactly the same problem and after replacing the control module, it solved the problem! But not after spending heaps of $$ on other items such as those mentioned here.