temp not sat at 90 Deg!!

danpayneuk

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Hi guys.

Well I read that the temp was supposed to sit at 90 deg. And when I bought the s3 I swear it did (only owned it a month). Anyways. Now it only sits just over the second line and at highest in the middle of this and the next (one before 90 deg). Sorry not to sure what this temp would be. It does seem to drop off slightly when idiling.

It also seems to take a while to warm up to it.

The car is an S3 1.8t 2000 plate

From the service history the water pump and thermostat have both been changed back in May. I changed the thermostat again just to be sure but still the same problem.

I think the coolant temp sensor has been changed too, as it green. Thats if Im looking at the right thing.
I was looking on the right hand side oh the engine, on one of the pipes. Does that sound right.

Im not sure what else I should be looking for so I hope you guys on shed some light on things.

Cheers

Dan
 
normally one of those 2 , Ive done both on mine and seems ok now. Might be worth doing the sender again just to be sure for £18 ish
 
ok. I have done the thermostat as that was my first thought. Will try changing the sensor then to see if that helps. If not could it be anything else?
 
Have the coolant pump checked - this is prone on Audi 4 cylinder models to failure due to a lot of them having a plastic impeller which can come adrift from the drive shaft and can cause cooling system problems. It is vital to check this as a failing coolant pump could be responsible for dodgy thermostats.

(Taken from Audi Driver Oct 2010 from someone with a similar problem)

Hope this helps mate

Best wishes

Chris
 
Mine sits between 70 and 90 depending how im driving does this mean I need to do the stat and temp sensor both or is there a fault finding process to decide which part needs replaced ?:unsure:
 
Mine sits between 70 and 90 depending how im driving does this mean I need to do the stat and temp sensor both or is there a fault finding process to decide which part needs replaced ?:unsure:

Hi there, the car should run between 86 and 94 degrees at all times, though the guage will onlu ever show 90degrees if it is within this range. If the needle is anywhere else it's highly likely the thermostat is faulty. If the sensor is faulty (and mine is at the moment) it will normally show either 90 or sit at the bottom on the left and works when it wants too!!
 
I changed my sensor today, and the gauge has started to sit at 90 more often, but still drops to about 80... maybe i need to do the stat too??
 
i changed both. changing temp sender stopped it dropping to zero but changing the thermostat didnt do much it still often sits between 80 and 90, given up trying to sort it now.
 
I will get the water pump checked to make sure. It shouldnt be that but who knows.

Cheers
 
interesting as this first started happening when i had the cambelt and water pump replaced, how would the water pump affect the temp not getting upto 90?
 
Mine also started happening after Audi replaced my cambelt and water pump, hmmmm.
 
In this weather (~11 deg C) It still takes about 15 minutes to get up to 90 deg. Once there it stays.
 
right quick update.

Went to buy the temp sender and the chap said there were 3.

* The temp sender,
*temp sensor switch for guage
*and one for the fan. I know the fan kicks in so didnt bother buying that one.

I know where the temp sensor is (green one). Its the other sensor for te guage Im a bit stumped on. Not sure where this one is located.

Going to hopefully change both 2moz evening.
 
Anyone able to shed some light on where the other sensor maybe hiding?
 
Out of interest, I have this VERY occasionally...

What sort of price are the sender and 'stat?
 
as fingermouse said.

Not alot at all.

Problem all sorted now. 30 second job to change temp sensor and problem sorted.

Will take the other sensor I got back as not needed now.
 
Which sensor did you replace in the end, the one on the head? (mines green)

I need to replace mine and got quoted £33.30 inc vat from audi, are you guys using non genuine parts?
 
Mine has recently started to settle at about 86 degrees. If I switch the engine off for a few minutes, when I start it up again the temperature will be bang on 90 for a short while and then soon drop down to 86 again.

Which part(s) is likely to have failed to cause these symptoms?
 
It was the one positioned to the right of the head in one of the pipes.

Yea it was the green one.

No didnt go to Audi. Went to ALS (euro car parts equivilant)
 
Don't mean to hijack but...

Mine has recently started to settle at about 86 degrees. If I switch the engine off for a few minutes, when I start it up again the temperature will be bang on 90 for a short while and then soon drop down to 86 again.

Which part(s) is likely to have failed to cause these symptoms?
 
Interesting thread even more now as this morning I had three loud beeps and a symbol showing fault in the cooling system :S
 
OK - normally:

If the temp doesn't get to 90 degrees, or only gets to 90 in traffic, then we're looking towards the thermostat. The reason here being that the thermo is open too much, or for too long. The temp sender doesn't tend to be faulty in this instance simply because it IS reading the temperature correctly, and displaying that temperature on the gauge.

Use VAG COM logging block 001 to determine exact water temp reading, or use channel 51 on the climate control info. (AudiWorld Tech Articles).

Thermostats are here: Audi - Euro Car Parts UK

Fitting guide here: How To: Replace the thermostat

If the dash temp gauge doesn't function at all, or is unstable, then that tends to point to the CTS being faulty. They do tend to be more sluggish in their function as the get old, but that's to be expected of electrical items. Changing them isn't a bad thing at all. They aren't expensive and I think that when the thermo is changed, the CTS should be as well. Crosses all the Ts and dots the Is that way.

Hope this helps...
 
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Just an update on mine, last week all of a sudden my car wouldn't get up to temperature and would fluctuate between periods of spirited driving and being standstill. I scanned the car and came up with an intermittent fault with coolant temp sensor (g62) in the engine module and Coolant temp sensor (g2) in the instrument module.

After reading a lot of waffle on other forums as I was searching specifically for my engine code, it turns out there are two temp sensors in one located at the side of the head. Pre 2000 seems to come with the blue 4pin sensor and pro 2000 green 4pin. Check what you have fitted before you go to purchase it just to be sure.

I changed mine this morning along with the o-ring and securing clip and as soon as I took mine out I could tell it was the cause of the problem as it was dirty and slightly corroded. The temp sensor cost just under £35 for all three items and now the car warms up as normal and sits bang on 90 degrees

:)
 
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quick update on mine , changed the stat , flushed the entire system , new stat and coolant £20 , dingbro stat comma fluid, now takes 10-15 mins to start rising but climbs slowly toward 90 deg then sits there all day , sat in traffic it will climb to 95 deg ( actual vag com reading 109 deg) then the fan cuts in goes back to 90 deg , if your doing the job yourself then the bleeding procedure for the cooling system is as follows

1) disconnect the expansion tank and prop up with a block of wood or similar
2) fill expansion tank to full
3) start car and set heater to HI with blower on half way
4) have assistant rev the car to 2500 rpm and hold for 10 - 15 mins whilst pumping all the coolant pipes including heater matrix

within 5 mins mine was air free heres hoping i get a few more mpg on next tank
 
Had problem with my S3 not sitting at 90 :no:

Changed thermostat today. Broke the dip-stick guide :unsure:(£3.51) Got to dark and cold so will bleed system and re-new coolant tomorrow and hopefully all will be sorted.
 
Meh, as far as I'm concerned bleeding the system requires leaving the cap off, quick couple of pumps of the top hose, heaters on full wack and let it warm to temp.

Done.

Worked fine for me the thousand times I've done it...
 
Remember if you have your heating on high the temp will sit slightly under 90
 
ahh we flushed the entire system back n forth for a while , the amount of rusty ***** that came out was bad looks like 9 yr worth of no coolant change ..........

old school yes .....

no bleed screw to be found ???

air system on high half hour later no heat ............. at idle .............

propped up the expansion tank . jacked up the car on same side ,.and revved car to 2500 rpm

problem solved in 5 mins .......


maybe just cos we flushed the entire system but end of day resulted in matrix air lock that wouldnt shift , im only stating how we resolved it and hope it helps other forum members .......
 
ahh we flushed the entire system back n forth for a while , the amount of rusty ***** that came out was bad looks like 9 yr worth of no coolant change ..........

old school yes .....

no bleed screw to be found ???

air system on high half hour later no heat ............. at idle .............

propped up the expansion tank . jacked up the car on same side ,.and revved car to 2500 rpm

problem solved in 5 mins .......


maybe just cos we flushed the entire system but end of day resulted in matrix air lock that wouldnt shift , im only stating how we resolved it and hope it helps other forum members .......

Yeah, that's fair enough dude, I wasn't slating you at all, everyone has their own way of doing it. Whatever works for you. :thumbsup:

There isn't a bleed screw on the 1.8T coolant system AFAIK.

I HATE manual bleed coolant systems. The 306 GTI springs to mind....
 
Meh, as far as I'm concerned bleeding the system requires leaving the cap off, quick couple of pumps of the top hose, heaters on full wack and let it warm to temp.

Yea i want to flush all the old coolant out and it was getting cold so job for tomorrow :yes:
 
:laugh:yeah manual bleed stinks lol , ive got 3 livers for sale dude not too sure if the doners will be happy to give em up tho lol
 
Changed my thermostat and coolant temp gets up to 90 and doesn't move :jump:

All sorted :thumbsup: