Water temp stuck on 60 degrees

[voteforpedro]

The needle on the water temp dial doesn't move. How can I fix this and what are the consequences of such a fault?

 

[Matt82]

plug it onto vagcom and see if the ecu is seeing any water temp

if not, its highly unlikely both the gauge and ecu temp sender are borked and youll have to replace the stat

if you dont, the oil wont get upto temp blah blah blah the ecu will see the engine as cold and richen it up and make it drink more. bore wash, loads of fun

 

[Bong Water]

Temp sender is easy to fit takes 2 mins so try that first, on my old A4 it didnt fix the problem and it ended up being the thermostat stuck slightly open which is still a fairly easy fix just slightly more expensive

 

[aragorn]

If its the stat the temp will usually come up if you leave the car idling for 5-10mins (once its hot)

 

[voteforpedro]

If its the stat the temp will usually come up if you leave the car idling for 5-10mins (once its hot)

I drive it on 45 min runs daily and it doesn't move but the car otherwise runs just fine. Coolant level is also still at max and it's been "stuck" for a few weeks now.

IIR, first time I noticed it, after I left the car for 20 mins after a long run, switched the engine back on and the temp was reading normal again. Now it doesn't move no matter what.

 

[aragorn]

When your driving, if the stat is jammed, the airflow thru the rad overcools the motor and it reads low.

If you get the engine hot (ie drive around for 10mins), then leave it idling for 10mins, you should see the temp rise.

If it doesnt rise, its likely to be the sensor or guage.

 

[DEEJAY TQS]

Mine never moves from 60 too,when driving, as soon as i stand in traffic it comes up a little but hardly moves, i did a oil and filter change using some magnatec oil and it doesnt tap now which is a bonus but i changed my plugs at the same time ,and they were very sooty, so maybe mine has the same fault????? if the car thinks its cold and its keeping the mixture on the high side,but my fuel economy is still ok at 32mpg average

 

[aragorn]

deejay: sounds like it, but then when our 1.8T was doing that it was only managing 24mpg...

The guage should point to exactly 90c at all times when its under normal operating conditions.

 

[DEEJAY TQS]

deejay: sounds like it, but then when our 1.8T was doing that it was only managing 24mpg...

The guage should point to exactly 90c at all times when its under normal operating conditions.

well ive just got in from a round trip of about 15miles,and the needle never moved from just above 60 degrees, it was in between that and the first notch on the marker, ill phone audi up in the morning and get a new thermostat and temp sender unit sent over, might as well replace them both then i know its done, also i seem to use a small amount of water, is this normal?? last month i topped it up from just below minimum and yesterday i topped it back up from mininimum again, it took about half a litre to top it back up to maxiumum

 

[aragorn]

Its not generally normal to lose water, but ours goes down to minimum and stays there too.

If i fill it up to max, few weeks later its back to min, but if i just ignore it, it stays at min and doesnt drop any more, so i just leave it at min!

 

[voteforpedro]

Holy thread revival, Batman.

So I've located the CTS, sprayed the plug with WD40 but it didn't help. The gauge is stuck on 60 degrees, doesn't move at all.

Also the radiator fan comes on immediately even when the engine is cold. Is the CTS confusing the ECU, or is it the thermostat? Please don't say thermostat...

 

[hardhitter]

Spraying Wd40 on the plug won't do any good.

Best thing i did when i bought mine was a new CTS and thermostat. Changed them with a new CTS housing, new G12 plus coolant and it runs bang on 87 degrees.

 

[aragorn]

The fan is unusual. If the ecu has noticed its faulty it might just run the fan anyway as a safety.

Although if you have AC, and its on, then fan will run for that too.

A new sensor is about 20quid, just get it changed. Didnt even lose any coolant when we did the two on craigs S4.

 

[Geeman]

Mine hardly ever moves from 60. When I first bought the car I thought it was broken.

Only in hot weather, or extensive stationary traffic does it ever move upwards.

When it DOES get hot, it never goes above half way though.

 

[aragorn]

Geeman: It is broken.

It will be the thermostat though, not the coolant sensor.

Get it sorted, because it will be drinking fuel and running in cold start enrichment all the time, which isnt good for the cat or the bores.

 

[Geeman]

Aaaaaah, so that'll be why it's running rich and wanting to stall all the time when I come to a stop...?

Nothing to do with the AFM being damaged in the fire then?

 

[Geeman]

So... in 'normal' circumstances, where (and when) should the temp gauge move to?

 

[Geeman]

Where is the thermostat located...?

[edit] Aaaaah, got it. On the end of the water-pump. I'm almost positive that I changed it when I replaced the water-pump and cam-belt.

Will switch it out again, just to be sure.

 

[Matt82]

pedro, have you worked out what the problem is yet?

use the climate control to see what the ECU sees the temp as, or vagcom. if thats showing 90* then you know its the sender

if thats showing low too, then its the stat. dont bother wasting time money and effort and diagnose is properly

 

[aragorn]

The guage should come up to 90 within a few miles, and stay there.

The dash has a buffer so the guage displays 90 for any temperature in the normal range of operation. So the engine could be at 85 or 95c and it will still sit at 90.

The stalling will likely because the ECU will only start to "Learn" once the engines in "run" mode. If its running in cold start all the time and never getting to run, then it will never start properly tweaking the mixture and idle etc.

 

[Geeman]

...so by replacing the thermostat, the stalling problem will be solved?

It's odd though as it only started doing it after I rebuilt the intake side of things following my engine bay fire...

 

[aragorn]

cant say for sure, but ecu will have reset its adaptive mapping when you disconnect the battery, so if you had the battery off when you rebuilt it that might explain it...

I know i had the battery off the car on wednesday or thursday, to clean the leaves out, and dawn only drove it to and from work the next few days, a journey where the engine barely gets up to temp. When i got in at the weekend the revs were dropping very low when declutching. Now though after driving to scotland it seems to have fixed itself.

 

[Geeman]

Okay, thanks.

Also replacing MAF at the same time...

 

[stub]

well i've got the same prob glad i'm not the odd one out. lol
i've ordered the temp sender this mornin so shell fit when i get it an let you know have it goes.

 

[gstevens26]

I've noticed that my temp guage sits between 60 and 70 and never goes above 70 unless the car is left to idle for a while. The thermostat was replaced earlier in the year because the needle kept showing 90 degrees but then just dropping to 60. This doesn't happen anymore but wondered if anyone can shed some light on my issue. Should I just change the temp sender or is it ok as it is??

 

[njsupplies]

Hi guys,

Ive had the same issue with my a3, wanting to stall when creeping along, drinking fuel, and no hot air, fan stays on after i tur the engine off too!

I changed the tempm sensor and it didnt do anything, having the thermostat changed today, so see what happens.

Did anyone resolve this?

 

[ian52]

Mine sat at about 65 in winter till i changed the stat. Sits bang on 90 all the time now like it should.

 

[phoenixv6quattro]

I have EXACYTLY the same stalling prob. Changed the throttle body, MAF, Thermostat, ETS, water pump, flushed the system, all related sensors, all the vaccum tubing/pipes.......Didnt do a ****** thing ref the stalling. I even changed the ECU. I'm going crazy now.......Wonder if a sledgehammer wil work..........

 

[njsupplies]

Just got my car back, changed the thermostat and its fine now! hot air coming out, and temp goes to 90 now!

 

[Matt82]

changing the temp sensor was a proper waste of time then........ why dont people diagnose stuff properly before chucking money at their cars?

 

[Geeman]

My new 'stat has arrived... along with a new MAF and connector. Will have to get them chucked on (along with the last silicon boost hose) and see if it makes a difference!

 

[DEEJAY TQS]

i went to halfraud and got a thermostat and 1 litre of antifreeze, was £7 for the antifreeze and £7.99 for thermostat, with my trade card i got both for £8.27 and the amount of different gaskets and o-rings in the box is unreal, must 12 in the box

 

[Geeman]

******... never thought of going to Halfrauds for a 'stat. Mind you, at £7 from the dealer, they aren't too bad.

 

[DEEJAY TQS]

******... never thought of going to Halfrauds for a 'stat. Mind you, at £7 from the dealer, they aren't too bad.

i think it would of been the same price then if i didnt have a trade card,but it would of cost me more in fuel if i had gone to the dealers as its 10 miles away, halfrauds is a 2 min drive from where i am

 

[Geeman]

Just been to pick mine up... but the MAF connector they ordered for me was the wrong fitment... not really surprised really. I bet the 'stat won't fit either when I get round to sorting it!