JBrown

so my tempture gauge in my cluster use to sit near the top bar and when i hit the dash it would go back down and sit normally at the low line . now all of a sudden if just stays on the top bar below the red zone, i have a lazer temp gun i checked the engine and the temputure is perfect. i noticed when i turn my fogs on the temp gauge goes a little higher and then when i tun my head lights even higher, and when i turn then off its goes lower. also when i turn the heat or ac fan level up the temp goes high too. i had my mechanic put a meter to the signals and they are good. do i need a new gauge or is somthing else the issue. i hate seeing my gauge so high even tho i know my temputer is fine i would just like it to work.

Rannem

Have the exact same problem in my -90 951..

Hope to get some input at this topic too

CDH-CTT

Check grounds, and wiring to temp sender in head.... I had a similar problem with my volt meter and I checked all my ground and found that the engine ground "looked tight" but when I touched it moved.... so removed and cleaned.... I know you said your tech checked them but check the grounds yourself....

Rannem

But isnt the problem related to the electronics inside the cluster? Im thinking since the gauge reacts to "knocking" on it?

JBrown

it use to react when you knock on it but that stoppped working lol

Lemming

My 968 has the same problem. I cleaned up all the body grounds and double checked the wires on the head. My guess is that it's in the instrument cluster but I have not pulled it yet to check. Mine still works with a tap or two!

dillon410021

I had to replace the gauge to get mine to stop. it was very annoying

AMCPILOT

Did you ever figure out what was causing your temp gauge to read high? I have a 1994 968 and your post is exactly what I am seeing in my car. I've tried everything I can think of and replaced more parts than I should an no change. If you have any thoughts, that would be great! Thanks!

DanaT

How did you replace the gauge and not the whole cluster?

dmcampbell

I had the same occurance. Ran a ground #14 wire from post nut on back of instrument cluster to ground post under dash on drivers side. Also added a #4 battery cable ground from the block lug under intake/ just behind DME temp sensor to firewall ground point in front of battery. All instrument problems solved and car seems to run better. Mike

CurtP

The gauges are individual. Once you have the cluster out, you can remove each gauge. I'm running 968 gauges in a 951 cluster.

AMCPILOT

Thanks for the ideas ... Will try the extra grounds dmcambell suggests. You have no idea the lengths I have already gone through and no change. Keeping fingers crossed.

dinodanny

I had the same problem. I was pretty sure the car was not overheating and that it was the gauge. Mine would also react to tapping on the cluster. I bought a used gauge on Ebay and installed it just yesterday. Problem solved! Once you get the gauge cluster out of the car the gauge swap is pretty easy. It took me all of 20 minutes. Separate the gauge cluster from the bezel, there are about a dozen screws that hold them together. Remove the two brass nuts and washers from the football shaped plastic pieces on the back of the cluster. Carefully pry the plastic pieces off the gauge. They're held in by two posts. The gauge will separate from the other side. Installation is the reverse. Check out Clark's Garage for the cluster removal instructions. And by the way, I was able to remove the airbag and steering wheel without actually disconnecting the air bag. There was enough slack in the wiring to get the steering wheel off and the cluster out.

AMCPILOT

I've not only replaced the entire gauge cluster with thee different ones, but also the gauge itself with two known good working ones. I've cleaned every ground in, under an throughout the car ... Dismantled the entire dash, replaced all temp, DME, and fan sensors, relays, switches and even the entire fuse box. I could go on and on with everything else I've already done. Aggravation is an understatement. By the way, everything else in the car works properly, even the exterior temp display.

Oh, I've verified by both IR temp and connected OBD Bosch tester that the car runs at the correct temp. The temp gauge pegs at the top when you turn engine off ... Otherwise it is always showing at the top of the normal range to the bottom of the Red no matter the exterior temp. It is as if the scale is off and the top normal line is actually the bottom normal line. Very strange.

User 52121

Ok old thread bump - dmcampbell I hope you're still around

You said "Ran a ground #14 wire from post nut on back of instrument cluster to ground post under dash on drivers side" - do you mean the actual post that the little 7mm nut screws down to, to hold the football down?