Temp gauge keeps moving

[dans_vz]

My temp gauge, once the car is warm moves from 1/4 up to almost half then back down to 1/4 again and it will do this over a couple of minutes, and happens mainly when im cruising down the highway, even on a cold night.
Also sometimes the heater on its full setting will blow out cold air, and other times it will blow out hot air as it should.
The coolant hoses under the bonnet dont seem like they are pressurizing because when the car is running at normal temp I can squeeze them easily. Would the cooling system need to be bled?
Any ideas? Thanks guys

[Morton]

Yup, that needs a good bleeding. Try getting it up to temperature with the heater on, and removing the radiator cap. You may find that a bit of water shoots out, but then just air. At this point top it up, and let it go again. If it's a V6 there should be a bleed nipple on the thermostat housing that you can release air through also.


But you have air bubbles or vapour lock 100% if the hoses aren't pressurising and the heater is fishy. Just remember to bleed with the heater on, and give the car a bit of a rev

I often get vapour lock after flushing the cooling system on my car, and the temperature will skyrocket within the first 5 minutes of driving. I just pull over, remove the radiator cap, top it up, and it sorts itself out every time.

[Dum*P*ster]

Might try this.. Once my Engine gets hot.. My Temp gauge goes halfway on the Gauge.. Then Thermo Fan kicks in.. But, if im driving without needing to stop, the temp sits at the Quarter mark, like I want it to.

But when it sits idle eg at Red Lights, it takes 15-20secs then the Temp Gauge goes Halfway then Thermo kicks in, and the Gauge lowers .. Once at low cooling It will take a few seconds to reach half way again and kick in Thermo.

Im assuming it needs a bleed, or a complete new Cooling system.. Who engine is stock as a rock from manufactor :P

At tho moment, Im looking at "Trying" to get Duel-Thermo Fans.. But I doubt I will have any luck. Mind need to find some small thermo fans from another type of car and make my own

But, I am DEFIANTLY going to be putting in a Thermo Switch, so I can turn it on/off when I want. But, if I forget to turn it on.. the ECU will turn it on when it reaches that temp :P Like a Normal thermo fan should!

[Morton]

Another good idea is a good Davies Craig fan for a pusher, with a thermatic switch independantly controlled. I run one of those on the front of my VQ, and love it You can manually select a temperature you'd like the fan to engage at, and it'll switch when outgoing water reaches that temperature. Handy for those hot days when you're giving it a bit of stick and the standard fans don't cut it.

[Dum*P*ster]

oooo, Where can I get one of them?

This has got my attention

BTW, Dans. Sorry for thread Hijack

[Morton]

Burson stock them. They're not cheap for good ones though. About $90 for a 12" fan, and maybe $50 for the thermatic switch kit? I'm just making that shit up, but it'll be somewhere in that ballpark.

[Dum*P*ster]

Either way, it sounds good. I don't mind spendin a lil $$$ on me hot sexy babe


LOL

[Morton]

Hahaha, you should drop a 304 in there The V8 clutch fans are unmatched in cooling ability!

I run my VQ between a full-throttle 3000-5500rpm for up to 30min at a time, and the temperature never crawls past half Granted, the car's moving at a nice pace, not doing burnouts.

[Dum*P*ster]

bet it wouldnt be cheap

And I just noticed you lived in melbourne.. I'd love to come down and see ya ride.. Looks like somthing I could get some ideas off