dead miss at idle speed
 

I need help! I have a 1992 190e 2.3 8v with a serious miss at idle speed. The car has 202k miles. When the car is cold, it idles great for 20 seconds. After that, it's like the choke turns off. I guess the cold start injector turns off. This is when it starts missing. It's very sluggish at low RPM's. It is also getting very bad gas milage, like 10mpg. It black smokes at idle and on take off. I've talked to several mechanics over the passed 3 months. I've even used some of this sites suggestions to no avail. I have checked fuel pressure and compression. I've checked the timing chain for slack and valve adjustment. I've replaced plugs, wires, fuel pressure reg, dis-cap, rotor, fuel injectors, all 4, O2 sensor, CIS temp sensor, thermo-vac switch. None of the suggestions have had any affect on this problem. please help?



1990 Montero 150k
1992 190E 202k
1997 BMW 328i 51k

Chcek your EHA current and/or differential pressure.

Thanks Steve. I found your write-up on "Evaluating Electronic Engine Controls" on this site. I'm going to give that a try this weekend. I'll let you how it goes. By-the-way, I know by reading my forum that it looks like I'm just a "Parts Replacer",but it's just that I don't have access to any trouble shooting tools. I do although have a book on the basic CIS fuel injection systems.
Thanks again, Greg
1990 Montero 151k
1992 190E 202k
1997 328i 50k

Steve, I borrowed a FLUKE 87 meter but I'm not quite sure where to check the EHA or Differential pressure so here goes. The connector, a two pin, on the firewall side of the fuel distributor has a reading of 41.5 with the key on and engine off. The connector, a three pin, on the radiator side of the f/d has a reading of 46.5 with key on and engine off. So what does this mean? HELP! Also where is the OVR located? Thanks Greg.
1990 Montero 151k
1992 190E 202k
1997 328i 50k

Steve, there was no change at all when I unpluged the two pin connector on the back of the fuel distributor. I'm still assuming that this is the EHA.