E36 Drivability Problems

[Hans Conser <conser@xxxxxxx>]

Hi all, greetings from Bozeman, Montana.

My 92 325i has major drivability problems, mostly when it is very warm, 
which has made it difficult to get it fixed I think because mechanics 
don't have time to drive it enough to make it do what it does:

*Severe* stumble at low RPM's on throttle tip in, missing at all RPM's, 
intermittent miss and roughness at idle.

What's been done:  

Fuel injectors removed, cleaned and tested; tune up with plugs & 
filters, new airflow meter ($$$), new O2 Sensor.

Coils, TPS, all test OK.

Early on in the problem I ran a lot of Techron through it too.

I am running out of money to solve this problem, so I am resolved to fix 
it myself, this after $800 to my mechanic for most of the above.

My mechanic says a bad coil that only shows up when very hot, so I have 
a coil ordered and plan to start swapping one at a time.  Would one bad 
coil cause the whole engine to stumble?

Today the check engine light came on briefly, and it was the code for 
the O2 sensor heater and heater relay.

I'm thinking the O2 heater should be good as it is so new, but am 
considering ordering a new relay, or maybe testing the current one, but 
testing seems like it could be a waste as the problem is intermittent.


Suggestions?


Hans Conser
Network Chiropractor
Boundless Health Chiropractic

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