Mercedes 190 2.3 16v-starts OK but keeps stalling until warmed up.
 

Car starts OK but stalls under load until engine warms up then idles/runs OK. Fuel pressure is OK , inlet air valve not sticking, no vacuum leaks. Seems engine temperature related but any help appreciated.
Thanks,

Check your cylinder compression. I had similar symptoms and the issue turned out to be a couple of burned exhaust valves.

Thanks for reply. Compression is within acceptable limits so it seems related to temperature or auto enrichment on Jetronic system.

does it have a oxygen sensor? I have been doing this for years,cleaning carbon off oxygen sensors with steel wool.But I learned my method was flawed. If your exhaust smell rich on the new fuel injected models.Start by removing sensor or sensors keep rear one marked.Soak in gasoline overnight to lossen carbon,lightly brush with tooth brush,and blow dry.RFe install,and enjoy your lost power.
Now sometimes you need to replace one.

wymlen:

The KE-jetronic system with which your car is equipped incorporates a potentiometer that senses the position of the air flow plate, and the rate of movement of that plate. The rate of movement is directly related to demand for a change in power. A rapid increase in power requires mixture enrichment; the potentiometer signal is used by the ECU to provide acceleration enrichment via the electrohydraulic actuator (EHA).

The EHA is a rectangular device with a two wire plug located on the side of the fuel distributor (FD). The first test is to unplug the EHA and drive the car from cold. No change? The cause of the problem can be in either the potentiometer, the ECU, or the EHA. If there is a change in the behavior then at least you know that the ECU and the EHA are functioning to some degree.

Begin with this and let us know.

All tests assume that the ignition system is in perfect condition, and that compression is good. Ignition faults can be misinterpreted for injection faults.