I reckon that my 1.05 1993 polo is overcooling. It never goes above 75 on the clock except when sitting in traffic for ages.

I have replaced the thermostat and both temp senders.

The only thing that I can think of is that the thermostat is leaking water into the radiator from start up and preventing the car from reaching its proper operating temp.

Is the thermostat only supposed to have 1 o-ring and does it sit under the thermostat when you are refitting or on top of it.

Also what does that sensor inside the air filter housing unit do.

Cheers for any advice as I cant understand why its doing this.

Edited 27 July, 200719 yr by Docbooze

yes the thermostat should only have one seal on it, but you should put the stat in the big housing first then the seal on top and then the other part of the housing (the 2x10mm bolt bit)

mine never gets over about 80 when in motion never has since i fitted new headgasket, theremostat etc etc. fan kicks in traffic tho.

the sensor in the airbox is for the hot air change over flap for cold running

Cheers for replies

Yeah I'm not really that bothered it's just one of those small niggles that you wanna fix. I cant really see what else I can do as I've been trying to find the problem before I fill up the radiator with antifreeze.

Solved the problem

Was it a faulty thermostat - no!!!!

Was it a problem with the temp sensors - no!!!!

Did knobhead here forget to properly bleed the system due to impatience - YES!!!!

Runs fine now solid at just under the 90 mark.