Please help at the end of my rope!
 

First, thanks to everyone who has helped me over the years.

I will make this a short as possible...

'85 500SEL, 250,000 miles. I cannot find the trouble; when I start it cold it idles extrememly rough. I have watched it as it warms up and it seems to go through the warmup process, i.e., idle adjusts as it warms up, etc. When cold, I can adjust the CO screw counter-clockwise (leaner) and it trims out. However, once it reaches operating temperature I have to turn it back clockwise (richer) to trim out.

Technical: New top end 6 months ago, rebuilt Lambda box, rebuilt OZL, Idle control box has proper voltage, idle adjuster checks out, battery voltage to warmup regulator. I have driven myself nuts hunting for vac leaks.

The only thing I am not sure about is I think my oil pressure sender is not working. I do not know if that makes any diff.

Anything else I should check? PLEASE HELP!

fuel pressure test time.

sounds like the warm up regulator is DOA.

Joe

Is the warm-up regulator repairable or is it R&R?

Check the "tweak" post!