Damian

Hi all:

I have a problem with the engine which manifests itself without consistency; the engine will stall, at idle or cruising RPMs on the highway, and I cannot get it to turn over after this for at least 1 minute at rest. New plugs, air filter....

My initial thoughts are fuel filter replacement but would appreciate some feedback.

Thanks,
-damian

Mercedes Tuner

I would replace the Fuel Pump Relay.

Benz_dude

As Mercedes Tuner says, a fuel pump relay or fuel pump.

Damian

Thanks - have a fuel pump relay on order; will update with results.

Damian

Unfortunately, after replacing the fuel pump relay and the fuel filter, I am still seeing the problem.

Next, I suppose, would be the fuel pump.
Could the problem be somewhere else?


Thanks in advance for your help.

sph17

You dont mention, does/did your check engine light come on? If yes, two things:

First, you might want to look into purchasing an OBD II computer to hook up to your engine computer to read error codes. This might give you an idea where to look.

Second, sometimes when an error code occurs, the computer shuts down and the car goes into "limp home mode" and it runs on 1/2 the cylinders. Turning the car off for a few min. ususally re-sets the computer to get you out of "limp home mode". Running on 1/2 the cilinders gives you no power and when you slow down for a lighht or to stop, ususally your car will stall unless you keep the revs up with the gas pedel.

Damian

thanks for the help sph17
check enging light is on - but its reporting an EGR valve problem if i recall correctly.

common sense would have me check again to see if any new codes are being reported - however, i dont seem to have a 'limp home' problem as the car does have power at all times...

thanks

Mercedes Tuner

On early 104 engines the EGR Pipe which goes from the throttle body to the EGR Valve, had a comon problem of clogging up with carbon, which could set this code. The EGR Valve is fine, you just need to remove the pipe and clean it out. I doubt this would be causing your problem.

I don't think it would be the fuel pump itself. Normally if the fuel pump quits working, that's usually it and it needs to be replaced. It would not usually cause an intermittent stalling problem.

I would check the crank sensor, or the cam referance signal.

autotech.ca

you mentioned in your first post
"the engine will not turn over for about 1 minute after it stalls"

are you saying the engine stalls, then it will not crank after ???

or the engine cranks but will not start ???

pay attention to the details, they are very important

Damian

ALL:
Thanks so much for the help.

autotech.ca:
the engine will crank, but not start.

Mercedes Tuner:
what particular qualities would i be looking for when checking the crank sensor/cam position sensor?

Mercedes Tuner

For this it would be easier to take to a shop or a dealer.

If you take it to the dealer, they can look at the actual data from the signal through a lap top.

If you take it to a shop, they would use a DVOM to look at the wave patter, or check the resistance on the sensor to see if it is good.

In order to check it correctly you need to know what the actual value should be so you can compare.

Either there is a break in the wire and only shows up when it gets hot, or the voltage of the signal is changing and is going out of range to where the computer can't see it and is causing the car to stall.

raskens

First time poster. I hope It works. I recently bought a 1994 c280 that had the same symptoms your car has. this car has been at a Mercedes shop 4 times for this problem at a cost of close to four thousand dollars. however this did not fix the problem. in my research I found a Mercedes service bulletin dated back in 1997 that described this problem. the stalling was due to a faulty over voltage protection relay. i have since changed the relay and no more stalling. this relay is located on the left side of your engine compartment, under the black plastic cover. It is about 3 inches high and 1.5 in square it has a 15 amp blue fuse on top of it. The part # is 0005405245 made by Siemens (Austria). The service bulletin goes under damage code 5443752. If you have this relay you need to change it. I tried to attach the bulletin but it did not work. Good luck.

raskens

This is the service bulletin from Mercedes.