Temperature Gauge Jumping, Engine Overheating

[craig4ie]

DOODS!

So my car usually runs at just under half temp after it gets warmed up, but last week she started run at a hair over the half temp mark unless I had the heat on. Today, I'm sitting in traffic and the temp just bounces (a couple times) from 1/3 to 2/3 on the gauge so I chuck the heater on to cool things down...which it does (to the half temp mark). I turned off the heat for a couple minutes and it did a couple more jumps so I got her home to check for leaks and I found nothing. I'll check the level after she cools down.

I'm thinking that this might caused by be air bubbles in the system?

Any Input would be greatly appreciated! The less time I spend messing around in the frozen dark ally...the better.

cheers,

Craig

[Jean]

Jumpy temp gauge - Possibly a bad connection at the temp gauge (check the rear nut behind the cluster), or bad connection at the temp sensor on the engine.

[craig4ie]

Jumpy temp gauge - Possibly a bad connection at the temp gauge (check the rear nut behind the cluster), or bad connection at the temp sensor on the engine.

hmmm, potentially, but that doesn't explain the engine getting hot

[Jean]

Nope, and thats why I noted above for the temp gauge.

[craig4ie]

Thanks for the input. The car isn't hot anymore so I went and topped up the coolant which was rather low. I'll run it and bleed it...hopefully this is all that's required.

[jflower]

make sure the engine is in fact overheating. I chased a similar problem for months, turned out to be the engine ground post had rusted completely and was not providing a good ground any more. The weird thing was the gauge would rise with engine load and turning on the heat would make the gauge go down. It was also jumping like you described.


Make sure the system is bubble free (if you're low on coolant again, there could be bigger problems), then make sure it's actually overheating, then check electricals.

good luck
jflo

[mikeedler]

It is probably your fan clutch. If it is only getting hot when you are sitting or going slow, then it is more than likely the cluch. with the engine off, spin the fan blades, if it spins around more than half way, the clutch is prob. worn out.
- if it is getting hot while driving too, could be a sticking thermostat.

bubbl3s just dont show up in your cooling system