Erratic temp gauge -not just on other electrical load- what?

[Dug Nichols]

My car developed an erratic temp gauge the other day, which seems to be intermittent. I've always had a temp gauge which moves up when I hit the brakes, a turn signal, or headlights, but just lately it started bouncing around independent of this. What's the best troubleshooting or likely cause??

TIA

[canadapierre]

Check all the grounds behind the dash. Might even want to add a new one to cover all the bases.

Pierre

[Mike Self]

1. Remvoe instrument cluster

2. Locate little brass nuts on the back side of the temp/fuel gauge housing.

3. Make a Y shaped wiring harness with ring terminals on the Y's short end and a spade or ring terminal on the long end.

4. install ring terminals under each brass nut (one for temp, one for gas)

5. Ground other end to body

6. Kiss twitching gauge problem boodby

cheers

mike

[danjrusdug]

It ended up being the ground strap from the battery to the fender. Once I connected it, all was fine. Check you ground to the engine as well.

Hope this helps.

Doug

'73tii Atlantik

'90 325i Zinnobrat

[mtriple]

When mine did the bounce when I hit the brakes..etc I cleaned up the ground contacts in the front from the battery to fender and the back where all the rear tail lights are grounded. It fixed the issue.

Good Luck.

Hamada

[ingraham]

those things will fix it. The cause of the intermittent fidgeting is the same as the electrical fidgeting -- poor ground connection at the gauges or in the battery ground cables. The intermittent thing is more likely caused by the gauge ground nuts.

[Dug Nichols]

Excellent! Good to know grounding is cause for the erratic behavior too. And thanks for the detailed instructions - much appreciated!

d