Where does your A4 TDi temperature needle sit?

[AudidriverA4]

Here's mine after a 20 mile spin:

My needle never quite the 90 degrees mark,

I'm just wondering could my thermostat be acting up?? or maybe ever TDi needle only goes that far?

Thanks

 

[smiler2012]

looks normal to me mate wouldn't think it be thermostat fault these are common for coolant temp sensors? if your worried i would just fit a new one 5 minute job

 

[marktdisport]

Yeah it looks good as long as it doesn't alter whilst driving I wouldn't bother...... It's near enough 90oc probably just the temp sensor

 

[AudiLeon]

My 2.5 sits bang on 90 but our 1.9 sits just below. Which i expect as the thermostat opens at 87.

 

[stu_m]

Mine sits bang on 90 after about 10 miles of town driving or about half that at motorway speeds

It will be a lazy stat causing it to not get to bang on 90

 

[Wahlstrom]

Just changed my stat on my 1,9 TDI. Mine never hit 90, unless I really gave it all, but it quickly went back to 70-80..

Now it hits 90 and stays there until engine stops
So could be Your stat giving up..
My stat didn't look faulty.. It was in closed position.. But still.. It was faulty

 

[AudidriverA4]

Thanks for all the replys again.

@stu_m if the stat is lazy could it still be working 100% fully?

 

[AudidriverA4]

Just changed my stat on my 1,9 TDI. Mine never hit 90, unless I really gave it all, but it quickly went back to 70-80..

Now it hits 90 and stays there until engine stops
So could be Your stat giving up..
My stat didn't look faulty.. It was in closed position.. But still.. It was faulty

Mine never falls back to 70 or 80,

I'm beginning to think it's ok now.

 

[Wahlstrom]

Mine was like yours just a little bit further from 90..
How is when You accelerate hard.. Does it then go all the up to 90*??

 

[AudidriverA4]

Mine was like yours just a little bit further from 90..
How is when You accelerate hard.. Does it then go all the up to 90*??

Yeah it accelerates ok I think, No it never reaches the 90 mark,

Are they difficult to replace?

 

[Jp-tqs]

Petrol engine here but similar! Just replaced my coolant temp sensor as it was either reading 90 deg or falling back to 50 deg, intermitant fault cured by changing the cts. Sitting steady at just under 90 is definatly a weak stat mate and engine wont be operating at correct temperature. Sorry but no idea how hard/easy a stat change is on a derv mate!

 

[AudiLeon]

Yeah it accelerates ok I think, No it never reaches the 90 mark,

Are they difficult to replace?

It took me 30 mins this morning. That includes unlocking the car, opening the door, the bonnet and reversal.

 

[Greeny233]

Mine usually sits bang on 90 but last week when the outside temperature dropped to -8 degrees and I had the heaters on full the gauge did drop a little (the same as your pic). Since the weather has warmed a little it's back to 90 again.

 

[stu_m]

Thanks for all the replys again.

@stu_m if the stat is lazy could it still be working 100% fully?

The stat will probably not closing properly hence the not warming up quick and not getting to 90

 

[chris1008]

Sitting just under 90 is perfect, Thermostats will open around that. Mine always used to sit there and seems most people's do too. but recently sitting a bit lower, possibly the cold but will keep an eye on it incase it needs changing

 

[Wahlstrom]

Should be on 90* no matter if its -40 outside..

 

[AudidriverA4]

The stat will probably not closing properly hence the not warming up quick and not getting to 90

Cheers again for all the replies

Yeah it does take a long time for the temp to even get close to the 90 mark,

I think I will stick a new stat into it.

 

[stu_m]

I would go for a genuine one I had two stats in before I stuck a genuine one in the other two where just as bad as the first one I took out and one of them you could actually blow through it once I removed it!

Its about £20 with a new seal from the dealers

 

[Wahlstrom]

+1 for genuine...
But the one I replaced was also a vw/oooo, so they do get faulty..
Paid £32 for mine, but its Denmark.. Home of highest taxes, V.A.T. and so on...

 

[AudiLeon]

I have a receipt here from Audi.
044 121 113 - Thermostat - 18.14 + vat
038 121 119 Seal - 2.42 + vat

 

[PhilW]

Dont look at the gauge. Its only an indicator. You need to log the actual temp on vag com or similar.

Youll find the temp can be about 70-80 degrees actual and look like 90 on the gauge.

Do the temp sensor and thermostat at the same time to be sure.

 

[Audi Doodah]

After having MPG issues and reading lots of info on this site, I thought I would share my experience.

I have owned my A4 Avant 1.9TDI Sport for 3 months now and recently did a calculated MPG (not DIS) which came out at 38 MPG average (mixed driving). Looking at the various mpg posts I thought this to be a little low so I got myself a cable and VCDS-Lite. This showed that my coolant temp was never getting above 82 C even though my gague was always solid at 90 C. As the coolant temp sensor has two resistors in it (one for ecu and one for gauge) I thought it could be dicky and it looked like any easy fix so I fitted a new one (£20 from GSF). Another check on VCDS showed nothing had changed but discovered that the dash gauge starts showing 90 C when coolant temp hits 80 C (as Phil W states).

Next, then, was the thermostat (£5 from GSF) which I tested before fitting in a pan of water on the stove. Using a thermometer, I could cleary see the stat opening above 87 C as stated. Fitting was fairly straight foward needing only a 10mm socket and extension bar. You will loose most of your coolant so it's worth doing a flush at the same time. Unfortunately, i had no hose pipe access so could only pour water through the system.

New stat fitted and out for a spin with VCDS and now I'm getting coolant temp readings of 88-90 C when up to temp so no more increased fuelling for a "cold" engine I hope (time will tell on the mpg).

Strangley, after parking up and checking coolant level, it had turned a dirty browny pink (it had always been clean pink) so there must've been a lot of crud in the engine block (if only I had a hose pipe). Checking the old stat in the pan showed only fractional opening when up to temp so this shows coolant was never circulating around the engine block.

Now, my question is, could this be causing overly high temperatures in the engine because coolant is static thus damaging head gaskets etc???

 

[stu_m]

If the stat wasnt opening and not circulation the car would overheat in no time at all!!

this is my needle after a 8 mile drive at minus 1°c once it gets there it doesnt move at all

 

[AudidriverA4]

Bought a new thermostat and seal yesterday evening and went to fit the stat this morning........

Looks like the toughest job I've ever attempted on my car

In the end I couldn't get it out....

I have a 1/4 inch drive socket set and was able to land the socket on the top nut...
but the lower nut I could land the socket on it but was not able to turn the racket...the set only came with about a 4 inch extension...

Think I'll order a 6 or 8 inch 1/4 drive extension and attempt this again
It very tight for room in there and had wires blocked the stat cover...Audi sure don't makes things simple for ya
But everyone likes a challenge

 

[starnon]

If you have the right tools, ie a normal ratchet set, it should be the easiest job on the car second to turning the keys in the ignition

Normally failed thermostats make the needle sit about 70. I'd be interested to see if it makes a difference to your needle as normally cars' temp gauges are dampened (otherwise they would constantly fluctuate as I found when I had a 'real' temp dial on my old track car) and are preset to stop at various intervals, ie dead centre, half over or under etc.

 

[AudidriverA4]

If you have the right tools, ie a normal ratchet set, it should be the easiest job on the car second to turning the keys in the ignition

Normally failed thermostats make the needle sit about 70. I'd be interested to see if it makes a difference to your needle as normally cars' temp gauges are dampened (otherwise they would constantly fluctuate as I found when I had a 'real' temp dial on my old track car) and are preset to stop at various intervals, ie dead centre, half over or under etc.

Yeah I have a normal 1/2 drive set of sockets as well ....I couldn't even land a socket on the nuts with the normal socket set to thick and awkard in there.

With the proper extension on my 1/4 inch drive set I should get it changed.......... Hopefully

What engine code have you StuG ?

is there a difference between awx and avf engines or are they all the same under the bonnet? apart from torque

 

[AudidriverA4]

Ooops must have deleted the orginal photo

but anyway

Replaced it this evening and now its like this :

I lost a lot of coolant and had none at the house I topped it with water....would it be ok to drive it when it is most or less all water cooling it for a few days till I get some coolant?

 

[glenandem]

hi pal,would be ok to drive but i wouldnt want to as like you say if you lost most of your coolant then it will be pretty much pure water with very weak antifreeze and firstly it will start to rust the inside of your engine but i think a few days youd be ok but i'd be more concerned with the freezing temps with the weather at the mo and ive seen water in an engine either crack them or push the core plugs out!
might be wirth trying to bang at least a litre of antifreeze in just for now.
i changed my thermostat the other day too and only lost like a half a litre as i had the new one ready in hand to swap with the old one as soon as i took it out.
ive noticed the needle on mine goes up to 90 and stays there now and the reason i changed it was because it had to be revved to get it up to 90 and even then it went back down to 70!

 

[AudidriverA4]

Cheers mate

I'd say there was just about a litre of coolant left in her

I'll suck what I can out of it tomorrow and top the rest up with coolant.......

Hopefully it won't freeze tonight

 

[glenandem]

think it would have to be very cold for the water in the engine to freeze but who knows with this weather were having at the mo,might get a heatwave tomorrow and more snow sunday!

 

[SilverSaloon]

60 ATM Poor MPG, New stat on the way.