Running rich, and yes I have used the Search!

[RagtopE30]

Hi everyone. I need a little help on an issue with my newly aquired 1989 325is. Here goes,

The previous owner had the head rebuilt which included a valve job and the machine shop took a very nominal amount of metal off the bottom to get it straight again. In the process of putting it back together they fiddled with every adjustment on the intake system.

The car runs great. But the idle bounces around 1k and at all times the thing is running very rich. So rich that I can literally watch the needle fall on highway trips. And anyone behind me can smell it, just ask my wife.

I have tested the temp sending unit according to Bentley and it is good. I have swapped in a known working AFM. I put a brand new air filter in. I checked the intake manifold and associated intake parts for leaks. I have even gone as far as opening one of the AFM's and attempted to adjust the spring tension to get the CO% under control. But no matter what I do it is running very very rich.

HELP!!

[jlevie]

The MPG gage falling towards zero and the engine running poorly can be the result of a fuel system problem. A rich smell from the exhaust doesn't necessarily mean that the engine is running rich as that can result from misfires for any of a number of reasons.

In this particular case, I hope you marked the AFM and can return it to the factory setting. If you didn't, toss that one in the trash and get replace it with an unmolested unit.You need to check the fuel system pressure, both statically and while driving, make sure the O2 sensor is within its service life (scheduled replacement interval is every 100k), make sure that the C191 connector isn't bad, and have a smoke test run to check for intake leaks. I'd also suggest that you get another DME and see if that makes any difference.