I have a 1987 190E 2.6 and upon cold starting, the engine runs like a top. Once it is warm and I come to a stop, it often stalls and it is sometimes difficult to start after that. The car at speed still runs fine, though. Has anyone ever experienced this, and what was the outcome?

I have seen this...I would start with the overvoltage relay. If that doesn't help, I would have someone check the fuel system to make sure that Lambda is still working.

From what we had in our old W124 230E, the same problem was encountered. The service technician said something about the fuel supply being ok when its cold, and then when the engine warms up - the fuel gets evaporated before its able to the combusted.

They changed the fuel pump and relay, and it worked well. I was sure they did replace something too, but I can't remember as it was yonks ago.

Maybe Benzmac may be able to recall something?

Definitly go with Benzmac. I would change the overvolt relay first. That will more than likely cure your problem. It worked for me. :)

where is the overvoltage relay
 

where is the overvoltage relay and hot much does it cost?

Re: where is the overvoltage relay
 

The overvoltage relay should be located directly behind the battery in the engine compartment. It is silver in color with a red top that flips up to expose a fuse on the top. To the left of the Overvoltage Relay is the Fuel Pump Relay, which is black in color. Prior to replacing the Overvoltage Relay, check the fuse to be sure it's not blown. If memory serves me correct, the cost on Fastlane (which is the best) is around $60.00. If this doesn't work I would replace the Fuel Pump Relay (about $70.00 at Fastlane) . I had a similar problem on my 1985 190e, and it turned out to be the Fuel Pump Relay.

Let us know how it goes.

Brian

1985 190e
1990 BMW 325i