Bouncing Temp Gauge

[rrossjr]

I just noticed something strange last weekend when I had the GT out on the highway. At speeds of <65 mph, the temp gauge works normally (steady reading at a little less than 0.5) However, when I run the car up to 70 mph (or more...) the gauge starts to oscillate between 0-1. When i slow down, the reading is back to normal. Anyone else ever seen this?
Ron in Indy
Oh yeah, for what it's worth, the fuel gauge (and all others for that matter) seem to be working normally.
Cheers,
Ron in Indy

[BQS4]

I'd check to see if the wire coming off the sender is secure. Had mine do that once, found the wire loose. At normal low speeds worked fine, but, at higher speeds, wind would buffet the wire and the gauge would bounce.

[rrossjr]

Originally Posted by BQS4 I'd check to see if the wire coming off the sender is secure. Had mine do that once, found the wire loose. At normal low speeds worked fine, but, at higher speeds, wind would buffet the wire and the gauge would bounce.

Thanks Gene,
That sounds reasonable, since it doesn't seem to be RPM related (only MPH)
I just had the @%&**~! instrument panel off last year to fix the speedometer. I will probably live with it until something else breaks back there.
Ron in Indy

[BQS4]

Originally Posted by rrossjr Thanks Gene, That sounds reasonable, since it doesn't seem to be RPM related (only MPH) I just had the @%&**~! instrument panel off last year to fix the speedometer. I will probably live with it until something else breaks back there. Ron in Indy

Ron,
I meant the sender in the engine compartment, on the thermostat housing.

[hrcollinsjr]

I had one that was doing weird things also. It turned out that the sending unit had gone bad. You could wiggle the terminal slightly.

Harold

[newman27]

I happened to notice that the FSM says to drain all the fluid out of the radiator to change the sending unit. It seems like that wouldn't be necessary. Is this just another FSM quirk?

Matt

[BQS4]

Originally Posted by newman27 I happened to notice that the FSM says to drain all the fluid out of the radiator to change the sending unit. It seems like that wouldn't be necessary. Is this just another FSM quirk? Matt

Yep....

[newman27]

Originally Posted by BQS4 Yep....

It figures... I know they didn't have PCs and Word Processors back in the early '70s when these manuals were being written, but there sure seems to be a lot of "cut and paste" errors...

[jlthunder]

I had a similiar issue. As Gene stated, check the connection at the thermostat housing. I had to put a new connector on the wire as the old one was so brittle, when I went to tighten it, it broke. A standard spade connector works on both styles. The one with the round connection and the one with the spade connection. Good Luck

[rrossjr]

Originally Posted by BQS4 Ron, I meant the sender in the engine compartment, on the thermostat housing.

D'oh! Of course, that makes more sense. I'll go out and check it later tonight. The good news is that I get to drive the car hard to "check the repair"
Cheers,
Ron in Indy