Been trying to solve a hard start problem on a 93 190E 2.3 . It will turn over for 20-30 seconds, then runs rich for a few seconds. Once the idle smooths out, it runs fine. It doesn't seem to matter if the engine is hot or cold. Here is a list of things I have
done so far:
1. Replaced OVP relay.
2. Replaced fuel pressure reg. (fuel leak)
3. Lambda 50-60%
4. Air plate static height 1.98mm
5. CIS temp. sensor ohms out ok.
6. Fuel pressure holding.(I think it was 5.5 bar while running and 3.5 bar with engine off)
7. Had dealer change wiring harness
8. Unplugged wire to cold start valve and also checked for pressure leak down .
9. No codes with code scanner.
10 Getting spark
11. New fuel filter,plugs,and 1 new resister on plug wire.
Any other ideas guys and girls? This thing can drive a person to drink. I'm sure I've missed plenty, hopefully something simple.
THANKS FOR ANY HELP!!!