kwikt

Trying to get rid of this bouncing gauge problem that popped up within the last few months on my 968. My gas gauge is very inconsistent and my temp and volt guage drops when I turn on the climate control fan. Strange that the temp gauge rises when I hit the AC button also even though both fans work!!!! New rebuilt Bosch alternator, new cables. good battery. cleaned and checked all grounds except for dash(this weekend) Radiator fans work high and low, new BLUE temp sensor. Seems like some sort of ground issue. I need more Ideas. Thanks

mytrplseven

I hope that the under dash ground is the issue. If not, pull the gauge cluster (not that hard) and take a pencil eraser to the contacts on the connections. Also check for a loose connector.

kwikt

The gauge cluster is coming out this weekend. I had it out before when I repaired my odometer gears. Hopefully bad connections.

gtroth

Clean the two grounds at the back of the engine (on top). That solved my temperature gauge jumps when big electrical loads were turned on. Presumably, there are currents flowing in that ground connection, and when the connection corrodes, it becomes a bit resistive. Ground current spikes from big loads produce voltage spikes across the resistive ground which result in measure to spikes.