Thermostats and Water temperature

[Wak]

HI Chaps,

1. Anyone know how difficult it is to change a thermostat and whats involved?

2. Anyone use the climate control Trick to see the actual coolant temps
http://www.wak-tt.com/climate/climatecodes.htm
(Works on the S4 Climate control with the same buttons.)

3. Could someone please tell me what temps their b5-S4 normally runs at and what oil temps. (Code 49C with the above procedure)




Why do I ask? I had my thermostat changed and on the way there temps were around 94-98 mark on motorway and normal driving.

afterwards temps were 100-105 on the same journey back.... the dash needle was above 90 as well and its was never off 90 before.

I have just had these symptoms happen with my TT and a new thermostat , luckily I had the old one , refitted it and all back to normal.

Now twice in a row on two different cars........I have a suspicion that the factory thermostat is better than a replacement oem one, maybe replacement thermostats are being incorrectly built with opening temps being higher!



:?

 

[hop2407]

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1. Anyone know how difficult it is to change a thermostat and whats involved?

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I've just had mine done - I reckon about 3 hours labour on my B5 A4 1.8TS.... I believe there's a fair bit of stripping down in the engine bay for a relatively cheap part. (My stat had not gone - It's a long story, search my recent threads (was having a water pump changed and decided to have the stat changed at the same time - Had a genuine part / stat put in)

[ QUOTE ]
afterwards temps were 100-105 on the same journey back.... the dash needle was above 90 as well and its was never off 90 before.

[/ QUOTE ]

I reckon somethings a miss - is the fan kicking in ? def's get it checked out.

[ QUOTE ]
2. Anyone use the climate control Trick to see the actual coolant temps
http://www.wak-tt.com/climate/climatecodes.htm
(Works on the S4 Climate control with the same buttons.)

[/ QUOTE ]

Never done it - don't want to tinker with something I might completely f cuk up and never be able to get it back to original settings - might be easy to do but hey, my choice I guess.

[ QUOTE ]
3. Could someone please tell me what temps their b5-S4 normally runs at and what oil temps. (Code 49C with the above procedure)

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Don't have S4 but I guess most are the same - Water / Engine temp always in middle 90, never goes over this on mine as I guess fan kicks in when it does

As for Oil, always a low reading when tootling around, however hard driving, oil temp increases to approximately middle of dial (120 deg is it - cant remember - don't usually take much notice)

Hope this helps.....

 

[Wak]

Thanks it helps,

the climate control trick wont mess anything up, it resets after an ignition off , its really useful give it a go, I use code 49c and keep an eye on coolant temps all the time.

I'll have another look at the fans but its too similar to not be the thermostat, your job was the pump which is also the timing belt so its a big job

I dont think its the fans really as on a motorway the airflow is much greater than the fans can pull in so it should have been cooler.

I hope a thermostat wouldnt involve a tbelt but I'll try to check it out tonight,

 

[ben21]

Sorry to dig up this old post, but i have a 1997 (P) A4 and am having trouble with the engine not reaching operating temp when driving. Got all the bits from audi thinking (according to haynes manual) it would be an easy task. However one of the housing bolts is inaccesible due to be behind some sort of housing (waterpump i believe). What else requires removal to get to this bolt???

 

[mwarrey]

Thermostat is not too bad to change on a 1.8t, a bit fiddly but no more than an hour tops. You do not need to remove the water pump (or timing belt!)for this as you can get at it from underneath.

Not sure on the S4, on mine I had it changed along with the timing belt a few months back. I seem to remember them saying it was not so straight foward on the S4. (Like everything else!)

I suspect your problem is the water pump itself not the thermostat. Common problem, the plastic impeller splits and works itself lose and you end up with high running temp. and eventually overheats. Same thing happened on my 1.8t.

 

[jimya4t]

ive got a 1996 a4 1.8t sport, my temp when driving stays really low at 60 but if i stop it picks up to normal temperature at 90 but as soon as i drive off it goes back down to 60??? any one know what this could be?

 

[Broken Byzan]

I would guess at the thermostat, its probably been changed to a pattern one at some point as they seem to run like that(mine does) I am goint to replace mine with an OEM one to see if that makes the defference

 

[joost]

ive got a 1996 a4 1.8t sport, my temp when driving stays really low at 60 but if i stop it picks up to normal temperature at 90 but as soon as i drive off it goes back down to 60??? any one know what this could be?

Mine was doing exactly the same, think the stat was stuck open. I changed the stat for one from GSF at the same time as I did the pump and timing belt/tensioners. It now goes up to 90 and stays there (obviously until I switch off...). Well chuffed.:icon_thumright:

 

[AndyMac]

Wak, why are you changing working thermostats to new ones that don't work?
My 97 A4 sits straight up 12oclock on both water & oil, never seems to move when at operating temp.

 

[jimya4t]

mine was fine wen i bought the car in the summer but wen the cold weather came in it sat at 60. so if i get one i need a OEM one?? is that a factory standard one?
cheers

 

[joost]

so if i get one i need a OEM one?? is that a factory standard one?

Not necessarily, you just need to make sure that the thermostat will open at the right temperature (87 degrees IIRC).

 

[Broken Byzan]

Not necessarily, you just need to make sure that the thermostat will open at the right temperature (87 degrees IIRC).

I have been there and tried that, maybe i had a dodgy one, but i have read of a few people going back to OEM 'stats for reliabilitys sake

 

[tracer]

i recently changed my thermostat because it had got to the point where the water temp never got above 60 -65deg. did a coolant flush and renewed with hellfrauds advanced coolant (pink stuff). since then it has been great, within a few minutes of driving its up to approx 90 for water and oil temps. what a bitch to get the bolts off for the thermostat housing, very little access to it, i eventually used a small socket and an allen key with a ball end to drive it. even worse to get it back in again and be sure its correctly in place. but its done now and that was the only niggly part , rest was easy.

my normal driving is to and from work and around town however i was doing a bit of motorway driving this weekend and found that when i sit at a steady 80ish mph the coolant temp drops to 60deg. have i still got a problem?

 

[InfamousAudi]

Does this climate control trick apply to the A4?

 

[Biglockie]

I've just changed the water pump, not too bad a job

 

[tracer]

Does this climate control trick apply to the A4?

yeah works for me but takes a couple of tries. something to do with the timing or how you press the buttons i dunno but it seems that i try a few times and nothing then all of a sudden up pops the first number on the display