Temp gauge dancing, stays low (1/4 mark), idle issues when cold

[streetwaves]

Hey guys. I've got a bunch of little annoying problems going on at the moment.

For one thing, the coolant temp gauge bounces all around. I tightened the nut on the cluster and it still does it.

The temperature is usually also quite cold - or at least it says so. Like 1/4 mark or a little more on the highway, after having been run for quite some time. Hardly ever goes towards the middle.

I recently had my radiator replaced. I also had the thermostat replaced a couple months ago.

The idling issues are strange. When the car is cold (just started up), the idle will be just a tiny bit over 500. Any time I let of the gas and push in the clutch, the idle drops really low like it's going to stall. After warming up, it gets better.

OH also, I've noticed a surging idle when sitting at a stoplight every once in a while. It'll be idling at 700 or so and then surge up to about 1K, and drop back down.

Any ideas?:???:

[rThor432]

The jumpy needle could be caused by bad solder joints. Those are very common. Check solder joints right by the temp gauge and at the base where the female connectors connect to the male pins of the mother board.

A bad/intermittent connection will cause the gauge to read incorrectly. The low reading could also be caused by the thermostat being stuck partly open at all times. Even new (usually cheap) thermostats can be faulty.. Advance and Auto Zone aren't your friends for parts like that.. Or it could also be a low temp t-stat. I bought a car from Texas and the t-stat was set for 65 degree C, or something like that. It would stay at the 1/4 mark and slightly above if I really loaded it up on a hot day.

I'd look for vacuum leaks causing the idle/return to idle issues. Outside of that, I could throw several reasons your way but it is hard to diagnose over the internet.. for obvious reasons.

Good luck!

[streetwaves]

The jumpy needle could be caused by bad solder joints. Those are very common. Check solder joints right by the temp gauge and at the base where the female connectors connect to the male pins of the mother board.

A bad/intermittent connection will cause the gauge to read incorrectly. The low reading could also be caused by the thermostat being stuck partly open at all times. Even new (usually cheap) thermostats can be faulty.. Advance and Auto Zone aren't your friends for parts like that.. Or it could also be a low temp t-stat. I bought a car from Texas and the t-stat was set for 65 degree C, or something like that. It would stay at the 1/4 mark and slightly above if I really loaded it up on a hot day.

I'd look for vacuum leaks causing the idle/return to idle issues. Outside of that, I could throw several reasons your way but it is hard to diagnose over the internet.. for obvious reasons.

Good luck!

Hey Thor, thanks for the reply. I'll check the solder joints. The thermostat is OEM. How can I check to see if it's sticking or set for low temp?

No vacuum leaks! I've had idling issues for a long time now and I've fixed every leak I could find. It's a pain in the ass for sure :(