E30 temperature gauge

[STRAWBS]

I have a small problem with my newly acquired BMW E30 320i coupe, the temperature gauge does not seem to be working I have checked the fuses, and the other gauges on the display work e.g. Speedo fuel gauge rev counter etc what could this be?

James

[r5gttgaz]

Temp sensor?

www.realoem.com/bmw/showparts.do?model=1152&mospid=47257&btnr=11_0755&hg=11&fg=35&hl=1

[thesilverfox]

a common problem with E30 temp and fuel gauges was the small nut on the back of the gauge come loose where it connects on the printed circuit board inside the dash housing. check this out after you have ruled out the sender unit

[STRAWBS]

r5gttgaz said:

Temp sensor? www.realoem.com/bmw/showparts.do?model=1152&mospid=47257&btnr=11_0755&hg=11&fg=35&hl=1

I have just changed the temp sensor but the temp guage still isnot working? but when the ignition goes on the temp guage moves up to the starting position on the scale but goes no further which makes me think that the nut at the back of the guage is still connected any ideas please

[STRAWBS]

ANY IDEAS??

[BliarOut]

STRAWBS said:

ANY IDEAS??

Have a look in the entire E30 electrical fault finding manual

400MB though!!!!! I downloaded it overnight.

HTH

[jagdpanther]

does it sit in the middle or at the bottom

[STRAWBS]

jagdpanther said:

does it sit in the middle or at the bottom

Directly at the bottom by the blue colour after it has risen from the pin suporting it when the engine is off once the engine is surned on it rises to the blue starting position but goes no furthure

if that makes any sence

[BliarOut]

Download the manual ^^ It'll give you expected values so you can tell if it's the sender or the guage.

[STRAWBS]

BliarOut said:

Download the manual ^^ It'll give you expected values so you can tell if it's the sender or the guage.

Nice one Mate"" i will download as soon as i get home. i will let you know

thanks

[jagdpanther]

My pa's 1988 520i does the very same thing...its very rare that his gauge hits the middle....

[STRAWBS]

STRAWBS said:

BliarOut said: Download the manual ^^ It'll give you expected values so you can tell if it's the sender or the guage. Nice one Mate"" i will download as soon as i get home. i will let you know thanks

the download keeps stoping halfway through

[M3 Mitch]

It would be very unusual for the engine to really run that cold but have you checked that? If the thermostat was stuck wide open...

Be careful with the digital stuff here, you may want to use a resistor, but in general you can ground the sending unit wire and the gauge should read full scale.

Check the resistivity between the 2 pins on the sending unit itself.

There is a connection under the intake manifold, in the wiring harness that goes back to the gauges, it's notorious for getting a coolant leak from the throttle body onto it and developing corrosion, bad connections.

Does the car run normally otherwise, does the heater put out normal heat? How's your fuel consumption? Does your oil smell of petrol (all these would be signs of running way cold)

I'd check that nut on back of the gauge too, your symptoms may be indicating the gauge is getting power and ground, but no signal from the sending unit at all. If the resistivity of the sending unit is normal, and grounding the sending wire does not change the reading, it's got to be a problem with the sending wire circuit, probably the nut or the above-mentioned connector.