Fuel gauge?

[Dazbag66]

Any idea my z3 1.9 1997 fuel gauge not working as not reading right shows 1/4 tank with yellow low level fuel warning light on no matter how much fuel u put in? Heard if take instrument cluster off and take fuel gauge out and clean the 2 pins the back so makes better contact using electrical conducting paste helps sort this problem any ideas cheers??

 

[colb]

Could try that to see if its that end at fault, other than that have you tried the hidden instrument test on the instrument panel to see if the guages fully swing when the test is run. If they do swing ok then fault most likely in the float unit inside the tank, the resitor part of it gets gummed up and fails to red correctly. Unit has to come out to clean or replace if its that.

Fuel pump and fuel level sensor Diagram for BMW Z3 E36 1.9 (1997) Catalog | RealOEM.com

BMW parts Z3 E36 1.9 Fuel pump and fuel level sensor

www.realoem.com

 

[Dazbag66]

Could try that to see if its that end at fault. other than that have you trird the hidden instrument test on the instrument panel to see if the guages fully swing when the test is run. If they do swing ok then fault most likely in the float unit inside the tank, the resitor part of it gets gummed up and fails to red correctly. Unit has to come out to clean or replace if its that.

Tried the hidden test and the fuel gauge did not move swing at all so poss is the gauge in cluster this z3 give me lots stress wow with miss fire fuel gauge fault and heater fan resistor

 

[colb]

Thats a good indication the guage in the cluster or its wiring have gone bad if it failed the hidden test. check the connections and clean them like you suggested, see if that sorts it. It may be possible to use the fuel guage from a salvaged car and just swop the fuel guage, at least you wouldn't run into the problem of coding a complete instrument unit.

 

[Dazbag66]

Yeah goin try it as not hard get cluster out so next job to do on the ever increasing list lol cheers

 

[colb]

Connections on the rear are a ribbon type cable that slots onto the circuit board if you haven't had one out before, disconnect and clean the board connection and spray electrical cleaner in the cable plug, ensure its a tight fit when reinstalling. As to the fuel guage to get at that its a strip down of the unit to see how its held in there, as far as I remember the unit can be replaced, not sure if any soldering is required to do that.

View: https://www.youtube.com/watch?v=Y01LjvlYGJE

 

[Sajk]

For others my car was off the road for a long time and the first time I drove it after it had had a complete refresh I ran out of fuel as the gauge was stuck. Rather than pull the sender unit out of the tank I have religiously used fuel system cleaner in every tank and this seems to have freed up the sender. Might help someone else

 

[Daspete]

I have cleaned the pins on the back of the fuel gauge in the cluster and that has worked in the past. Can get a bit of corrosion in there

If you need to get a new cluster, get one from a car with similar mileage. Should have no issues just being plug and play. No coding etc.

I changed mine to one with 3k higher mileage and had no issues.

 

[jaguartvr]

I think you get a warning dot appear on the mileage to warn that the cluster has been swapped.

 

[Daspete]

I thought that but I didn't get one. Hasn't it got a tolerance of so many miles anyway

 

[Jams]

Interestingly, I've recently had an issue like this, but all gauges (temp/fuel/rev/speedo) stopped working at the same time. The rest of the instrument cluster works fine.

Opened up the cluster and found what looks like two blown capacitors on the circuit board. The only thing I can think that blew these was accidentally hooking the car battery up to a 24V charger by mistake (? maybe someone will have more of an idea than me on this). Anyway, I'll be off to get these replaced this week and see if it solves the problem.

 

[colb]

Odds on the 24v blew them hope you fix it

 

[Mike Fishwick]

I had this problem, the guage reading almost empty, and the warning lamp operating in spite of knowing the tank was almost full. Living in the south-west, where 97 octane was diffcult to find, I had been forced to use 95 octane, and had not used the car for ages.

Are using 95 octane fuel? This, coupled with a long period without use, can gum up the sensor. Try running the tank down, and refill with 97 octane. I found that this freed up the sensor, and after years of irregular use I have had no problems, but here in France 98 octane is commonplace.

This is not an unusual problem, and is covered in a BMW Service Bulletin, the official answer being to fit a new type of sensor, with gold-plated contact.