oil level gauge

[petes90964]

Just had my 1990 964 C2 Targa sitting for three weeks and found that after driving for arround ten mins that the oil level gauge had not moved from below the bottom line.USUALLY GET GOOD READING after this time when I pull up to a set of lights.

Oil temperature was good and pressure good popped the lid and checked level within both marks on dipstick
with engine running.

Switched off engine and restarted
gauge moved slightly up from rest but still not to bottom level, let car idle for 10 mins nice and hot
front RH wing hot, fast oil cooler fan came on, pressure still good gauge still not moved.

Drove for around for ten mins temp dropped to normal, pressure still normal
stopped car and checked oil level with engine running, again still between both marks on dip stick
gauge still not moved.

Question is it the sender unit stuck with the car sitting around and not moving
giving me a false reading,
Or is it the gauge that has packed up

Will I try to clean up connector to sensor unit, maybe an earthing thing not sure if this will make any difference,
Also unsure if when I earth the wire to the sensor should it then read to the top of the gauge or the bottom
or will I have to pull out sender to move float up and down with the body of sensor earthed to check that there is then a movement on the gauge

Anybody out there with any other ideas before I get my hands oily

Thanks Pete

 

[tim_haskins]

Hi Pete,

I would check the level sensor located in the rhs wheel arch, It fits into the oil tank. If i remember correctly there are 2 nuts holding a cover plate and then a few nuts behind the cover plate to allow you to remove the sender unit. I dont think you would need to drain the oil but i would put a bowl under the tank anyhow. The sender unit is float on the end of a rod connected to a coil. As you move the float up and down the gauge should move. I would try doing this first to see if something is stuck .If there is no change in the gauge i would put a multi meter on the wires on the sender, set your meter to ohms and move the float up/down to see if the resistance changes.If it does then your sender is ok and is probably your gauge.....my money is defo on the sender unit as a few others have had the same problem

Tim

 

[petes90964]

okay tim looks like I will have to break out the spanners after this warm spell of weather has ended
will use dipstick till it gets wet

pete

 

[petes90964]

Job Done

Thanks for fitting instructions just about 1/2 litre came of oil came out but engine hot at the time as I also thought it would be a good time to do an oil change.
Old sender unit was made only in sept 2003 it was not stuck, float was still good but no reading on mulimeter for ohms was seen.
New seal and sender fitted outside of new sender coated in copper ease, Cover wire brushed and repainted wiring reconected drained off all oil refilled and topped up gauge now reading perfectly to dip stick
over all time 2hrs easy diy job

Thanks Pete