325 ROUGH RUNNING AFTER THERMOSTAT CHANGE!

[cbn2000]

I need some help with this one,

I've just changed a on my 91 325. Running sweet beforehand (but not reaching full temp). After re-fitting the thermostat housing, I tried starting, but the engine would barely fire. I then noticed a black wire that should fit behind a 10mm housing bolt that I'd left off. I touched this against the engine (ignition on) and noticed a spark on contact (wire runs to plastic injector/ignition coil wiring housing). I re-fitted the wire. Upon re-start, engine started but sounded like it was running on 4 or 5 cylinders. It now runs so rough it's undriveable. I've checked that no obvious cables have been disturbed - that one wire is the only significant thing I touched! - much appreciated if anyone can help.

[96_323]

When you started the car without the earthing wire you would of blown several fuses.
Is there any of the other electrics in the car not working? I.E. Windows, sunroof, interior lights?

[cbn2000]

Thanks for the reply. All other electrics are fine, checked fuse box - all ok. Disconnected battery and re-connected, no improvement. I've been informed by a BMW garage that the wire in question is the main engine management earth, and that I may have damage the ECU. I'm not yet 100% convinced by this. Still stuck, I think I'll end up plugging in to a diagnostics check to understand the problem.

[96_323]

They are right about it been the ECU earthing wire unfortunately.
Try the diagnostics scan and let us know how you get on.

[cbn2000]

[quote="96_323"]They are right about it been the ECU earthing wire unfortunately.
Try the diagnostics scan and let us know how you get on.