Water Temp. Sensor question

[mistermoto]

BMW E30 316i (M40 engine). I had the injectors cleaned etc. and replaced the water temp. sensor (blue) and it started fine until a LOT of black smoke ! Running mad rich ! As far as leaving soot on the garage floor. Eventually it was nearly unable to start. I disconnected the water temp switch and problem "solved" - meaning no black smoke - not starting rich or soot. Of course this is hardly a "fix" (it does idle a but rough when cold, of course) but what could be the problem?? Any ideas?

Also the care sputters a mid rpm (3.500-4.000), then it goes... if it does Other than that, it idles steady (a little bit rough), and runs smoothly -as if new.

Thanks.

[Grrrmachine]

Sounds like you may have a duff sensor. Best check it, following this procedure:

http://www.e30zone.net/e30zonewiki/inde ... emp_Sensor

[mistermoto]

Sounds like you may have a duff sensor. Best check it, following this procedure:

http://www.e30zone.net/e30zonewiki/inde ... emp_Sensor

Humm... Although i have not tested the new one, i put another new one in - same problem.

[reggid]

you got the right P/N?

[harry_p]

How long have you owned it?

Could someone have fiddled with the afm adjustment screw to compensate for a problem with a diff sensor / injector which is now causin overfueling after they've been cleaned and a new sensor has gone in?

[Grrrmachine]

You really have to test these parts; cheaper units can and do have faults.

Once you KNOW it's fine, you can follow harry's advice about a previous owner masking a flaw by adding another.