Temp gauge not working?

[motorsports_3]

Hey, I do not think my temperature gauge is working. When I turn my car on it springs to the first line but I never see it go above that. I ran the car at idle for 15 minutes and it didn't seem to move. In case it matters, I have an M50 with the low temp thermo (e30 325 one) and low speed fan switch (e36 318i) with no mechanical fan.

[Jean]

Did it work before the swap? Can you reset your si lights... is your ground nut present behind the temp gauge?

[motorsports_3]

Did it work before the swap? Can you reset your si lights... is your ground nut present behind the temp gauge?

Yes it worked before the swap. My Si lights are green right now. I am 99% sure the ground nut is there. Now that you mention it, it may be loose, which causes this problem sometimes, right?

Edit: I just checked the nut is there and tight.

[Adrian_Visser]

You're sure that you have the pins right on your wiring adaptor?
Did you use the e30 brown temp sender?

[motorsports_3]

You're sure that you have the pins right on your wiring adaptor?
Did you use the e30 brown temp sender?

I'm pretty sure I got the pins right, atleast via the diagram, and everything else works.
I am not using the e30 temp sender. This may be dumb but am I supposed to?

[ethrty]

yes you need to tap hole to to fit an M20 water temp sensor into the head. I havent done this yet either so dont know the best place to put it etc someone else may chime in there

[motorsports_3]

So your guage doesnt work either?

After doing some research, I cant belive I missed this. So I need to replace that sensor with the brown one in order for my gauge to work. Besides that the res of them are fine? What connector do I have to use for the 1 pin brown connector?

[ethrty]

So your guage doesnt work either?

After doing some research, I cant belive I missed this. So I need to replace that sensor with the brown one in order for my gauge to work. Besides that the res of them are fine? What connector do I have to use for the 1 pin brown connector?

Sorry, you wont have to tap a hole.. thats just for M52 (OBD2) engines. On your engine, i believe it is as simple as swapping out the E36/E34 sender for the cluster to an E30 M20 one. Not sure if you will need to rethread the hole or not, i havent researched these finer details of an M50 conversion, just the M52 conversion. Hope that helps anyway.

[motorsports_3]

Thank you, any help is good help. I looked at my head right now and have in order from the firewall, the TB heater hose, a black connector, and a blue connector. Do you, or anyone else know which one to replace, and do I just use the stock harness peice that was connected to that one?

[ethrty]

Im confidenet 5 minutes research should bring up which of those two senders you mentioned is for the fuel gauge and which is for the ECU. when you find which one it is, pull that and, if its the same connector as the brown top M20 one then try screw in the M20 one and plug it up.
As i say, not 100% revised on the topic, may or may not work and be THAT simple of an install.

[Gnarles]

Replace the black top sensor with the brown top m20 sensor. The blue top sensor is for the DME.