Author Topic: Temp Gauge Issues - I need Help! (Read 4355 times)

cabin · « **on:** November 27, 2009, 12:12:41 PM »

Here's the issue, my temp gauge does not work at all when the car is started, it just stays in the "blue" and will not budge. However, when the ignition is turned to acc. the gauge will go all the way into the red and stay there until the car is started.

This all started after doing the mess under the intake mod. Before this, the gauge worked as it should. I am thinking that maybe I forgot to connect a ground, or something got bumped.

Before anyone asks, the plugs are not switched for the two temperature sensors on the head, I have made sure of it. I should also add that both of those sensors are brand new, thinking that they were the culprit.

I really have no idea where to go from here. I checked all of the wiring and it looks just fine, no exposed wires or potential locations for shorts.

If anyone has any ideas, throw them out there, I am sick of chasing this stupid problem! At this point, I am thinking about just buying an aftermarket gauge, but I would really like to avoid it.

Choking Hazard · « **Reply #1 on:** December 02, 2009, 09:07:08 PM »

Totally coincidental bad ground on the back of the cluster? Could be a result of sitting for a while maybe, IDK...

DesktopDave · « **Reply #2 on:** December 02, 2009, 09:26:29 PM »

Put the old sensor back if you still have it. It's not the last time a brand new sensor was out of calibration.

vpilarry · « **Reply #3 on:** December 03, 2009, 10:57:49 AM »

I once accidentally swapped the temp plug with the oil pressure plug - gave me weird indications. Check that.

cabin · « **Reply #4 on:** December 04, 2009, 08:55:03 PM »

Quote from: vpilarry;82434

I once accidentally swapped the temp plug with the oil pressure plug - gave me weird indications. Check that.

This is exactly what it was. I somehow remembered that I had the oil pressure switch unplugged (no idea why) while the temp sensors were also unplugged. Well, two black, single pole plugs, visually identical, you can see how this would happen.

This just proves the point that you should label everything when taking stuff apart! I know I will from now on.

The E30 is back in business now! Coolant is properly bled and operating at an acceptable temperature. She is running great, even drove her to work (50 miles round trip) a couple days ago since it was halfway nice!

Thanks to everyone that has responded, I appreciate it.

Chalino · « **Reply #5 on:** December 14, 2009, 02:24:43 PM »

I have a question regarding the two coolant temperature sensors on the head; I just bought the car and the temp gague is not working. I've noticed two sensors on the head and know one is for the gague and one for Motronic but I'd like to know which one is which. One is blue and one is brown....

Wizard · « **Reply #6 on:** December 15, 2009, 08:38:54 AM »

Front sensor (blue) is for the DME.
Rear sensor (brown) is for the gauge.

Chalino · « **Reply #7 on:** December 15, 2009, 10:41:02 AM »

Quote from: Wizard;83040

Front sensor (blue) is for the DME.
Rear sensor (brown) is for the gauge.

Thank you!
I'm going to replace these and hope that fixes my gague issue. Unless the problem is switched connectors....I noticed some are only 1 pin while one of the plugs has 2.

DesktopDave · « **Reply #8 on:** December 15, 2009, 06:44:45 PM »

Let us know how it turns out. The sensors are probably the trouble.

If that doesn't fix it, the gauge itself might also be bad, or there's a little grounding nut on the back of the cluster that loosens up and flakes out the gauge. There's another grounding nut for the fuel gauge in case that one goes wonky too.

nigel · « **Reply #9 on:** December 27, 2009, 11:59:09 AM »

Which one is the oil sensor plug?

Chalino · « **Reply #10 on:** December 27, 2009, 12:58:23 PM »

Quote from: nigel;83692

Which one is the oil sensor plug?

I would like to confirm this as well. Out of the three similar looking plugs, two of them are 1 pin connectors while the third has 2 pins. The way I currently have it connected, the 2 pin goes to the blue temp sensor, the really short connector goes to the brown temp sensor, and the other 1 pin goes to the oil sensor. Is this correct?