Temp gauge reading low

[Andy J]

My A4 2.0 temp. gauge is barely moving even on my 6 mile commute to work, this is backed up by the car hardly heating up inside, normally I would suspect the thermostat but before I fork out £50 plus for a thermostat I would like to know if there are any other things to look for first.

Also how difficult is it to fit a new thermostat, on most cars I have owned it has been simple but Haynes give it a difficulty level of three spanners, this is the same level they give changing the clutch

[kite]

Could be the temp. sensor, but with the heater not blowing hot prolly the 'stat

[RickT]

More than likley the thermosat... HOWEVER if the thermo sat is staying closed the engine temp should go upto 90'c after 10 mins or so of driving as the collant will not be running around the engine..

The themo is a bit of a bugger to do.. but easy when you know how when you have the alternator off..

The coolant temp sensor also has a syptom of reading the engine temp lower than it is..

If you cant do it your self, let me know and i can sort it out for you via a mate.

Cheers

Rick

[Andy J]

More than likley the thermosat... HOWEVER if the thermo sat is staying closed the engine temp should go upto 90'c after 10 mins or so of driving as the collant will not be running around the engine..

The themo is a bit of a bugger to do.. but easy when you know how when you have the alternator off..

The coolant temp sensor also has a syptom of reading the engine temp lower than it is..

If you cant do it your self, let me know and i can sort it out for you via a mate.

Cheers

Rick

Cheers Rick, I would suspect the Thermostat as the car is not getting warm inside, after 10 mins it should be nice and cosy inside, plus it warms up when stood still and cools down when moving.

I should manage the thermostat myself I'm just confused that Haynes should give it the same difficulty level as changing the clutch.

[STEWY L]

it would seem that the thermostat is stuck in the open position, allowing the coolant to circulate through the rad,instead of keeping it confinded to the block/head when cold,as
suspected above.
if you haven't changed one of these thermostats before you will be suprised by the look of it
as it isn't anything like a"normal" one.
i would suggest you try a search, as it needs to be "located" correctly,and be very careful
when tightening the housing (plastic),i believe,and is easily cracked apparently.
i haven't done one myself,i'm only going on what the forum members have shared in the past, which shows the value of the "search" facility.
regards,
stewy.

[bez101]

it can be done with alt in place but fiddly ill take alt off next time will get to it much easyer

[RickT]

Cheers Rick, I would suspect the Thermostat as the car is not getting warm inside, after 10 mins it should be nice and cosy inside, plus it warms up when stood still and cools down when moving.

I should manage the thermostat myself I'm just confused that Haynes should give it the same difficulty level as changing the clutch.

I have a themosat in the boot of my car which i took off a few weeks ago thinking it was faulty.... (it turned out to be the head gasket)

The themo sat had only been on the car for 6 months!! LOL!!

Never mind!

Ensure you had a breaker bar to release the tension of the alt belt..

Cheers

Rick

[Andy J]

Ricky, now you've worried me, I've just had a little play under the bonnet just to familiarize myself with the task, doesn't look too hard. Now the bad bit, I removed the oil filler cap and noticed a very small amount of emulsion on the cap, the dip stick shows clean oil and the water has no sign of oil in it So I'm hoping it's the result of the cold weather as I haven't used the car for a couple of days.

[RickT]

Ricky, now you've worried me, I've just had a little play under the bonnet just to familiarize myself with the task, doesn't look too hard. Now the bad bit, I removed the oil filler cap and noticed a very small amount of emulsion on the cap, the dip stick shows clean oil and the water has no sign of oil in it So I'm hoping it's the result of the cold weather as I haven't used the car for a couple of days.

Give the oil cap a clean and then check it again after around 10miles... then 50 miles..

When the temp gauge is at 90'c does it blow totally cold??

Cheers

Rick

[Andy J]

Give the oil cap a clean and then check it again after around 10miles... then 50 miles..

When the temp gauge is at 90'c does it blow totally cold??

Cheers

Rick

The temp gauge barely moves above 50 but the heater does blow warmish but not enough to make the car comfortable especially in last weeks cold spell.