RE: <E30> Quirky fuel gauge

["Fadeev, Alex" <alex.fadeev@xxxxxxxxxxx>]

Daniel L Adams [mailto:dadams@domain.elided] wrote:
> 
> I have an interesting problem with the fuel gauge on my 1987
> 325IC. It gets stuck on "full" when I start the car. Sometimes 
> tapping on the front of the dial (in true Hollywood style :-)
> brings it to the correct level, and sometimes it drops to the
> correct level on its own after driving for a while. Like all 
> good problems, it's intermittent.

Daniel,
I am totally guessing here as I never had this problem on my E30. When I had
the instrument cluster out I noticed that both the temperature and fuel
level gauges are bolted to the cluster board. The temp gauge uses that
connection for the ground and goes haywire when that connection gets
intermittent. 
Could the fuel gauge be also using the mounting bolt for the ground? If it
does, try tightening the hex nut that holds the gauge to the instrument
cluster and see if that helps.

> Here's the quirk though...  If I press, and hold down the 
> trip milometer reset button (the mechanical one, not the OC),
> the fuel gauge shows the correct level! When I release it, 
> the needle springs back to "full" again.  Weird eh?

Not if you have a bad connection somewhere that is completed by the pressure
applied to the instrument cluster innards through the trip mileage reset
mechanism.

good luck and let us know what you find,
alex f

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