Am looking for some guidance with my 93 190E 2.6. It starts fine when cold, but after driving for a short distance, say 5-10 minutes, it starts to idle rough and will usually stall shortly after this. Whether it stalls or not, it won't restart again when the engine is warm. It tries to turn over but can't.

I've already replaced the override relay and had a Merc dealer do an hour of diagnostic time, looking at the sensors, relays, etc. They told me it didn't have any error codes in the computer. The only thing they found was a loose distributor cap with some corrosion, which they corrected. It ran fine for a couple of weeks, but now we're back to the same old problem.

We love this car but it's frustrating not to be able to drive it without fearing getting stuck somewhere. HELP!!! Many thanks!

 

i don't know wether this helps:

Engine does not respond to throttle. Surges when idling.Dies (outer temperatures
<approx. +10 °C). Engine cannot be started again (battery discharged)

Cause: Intake manifold preheater relay burned.