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[bruce]

I am getting an intermittent problem on my 88 325ix where the car seems to revert to running on about 2 cyclinders. Initially we found a harness connector (to the fuel injectors) below the manifold that had corroded contacts from a leaking coolant hose. Those I cleaned, reconnected and everything worked fine for about 2 days. I disconnected it again, sprayed contact cleaner, scraped, and reconnected -- lasted about 2 days. Since then the time frame is decresing.

Just before it happens, the temperature guage fluctuates wildly and then "ocillates" in direct response to the engine speed. Bam -the engine acts like it's a 2 cycle. I know now that I can disconnect and reconnect that harness, start the car and go.

Unfortuntely, it only lasts a short time before it does it again. For obvious reasons I only drive around the neighborhood at this point trying to find the obvious.

Other facts -- 1) the temperature guage has been acting strange for a while (fluctuating), 2) I can pull the "check system" fuse and immediately create the problem, 3) I can disconnect/reconnect the harness and it seems to "reset" things, 4)a couple months ago I was having battery problems and had to jump the car using a battery charger. A couple times during the ignition cycle, something (relay?) was chattering and causing all dash lights to do likewise -- may be totally unrelated.

So, I'm having trouble believing that the root of the problem is a bad harness connector. I think it certainly contributed, but it appears clean and tight. Is this a symptom of some faulty sensor and/or the ECU? I'm inclined to find a used ECU and go from there. Help.