Overheating Again!!

[myrichdad]

Hi all,

to cut a really long and protracted story very short been having major probs with S3 overheating & losing coolant (related I'm sure)

Audi/insurance Company ruled out head gasket failure suggested dodgy water pump and temp sensor

Mackenzies replaced water pump as a warranty item (it was only fitted 10k ago)

problem remained and is now really bad. I mean it'll last about 2 hours sometime without needing a couple of litres of coolant.

There is no evidence of coolant loss at any level at all (i have searched the drive so many times in the ams to find some, figuring it must be coming from somewhere.

I do have white smoke (sometime s quite thick) and a slightly rough idle.

I read somewhere else that the rough idle could be caused by temp sensor faults? why's that?

When i opened her up yesterday as it just reached 100 degs the fans were not even cutting in.

Is this controlled by the same temp sensor.

If so thinking of swapping it myself and then going on from there.....

the saga continues...please help.

Ta.

Kev.

PS What's the part code for the temp sensor - anyone know - is it ieasy to fit...

 

[god_thats_quick]

Do you mean 100 degrees on the dash or on the non adjusted climate control value? The real temp is pretty much always over 90 on my S3 and the fans don't kick in untill around 103 and I have seen the temp go as high as 108 (hot day and stop start traffic) without the dash moving and this is normal!!! I think the dash is basically a cold - normal - ******** guage with no inbetween.

Have you had a compression / pressure test as the only way I can see the water going is via the engine and out the exhaust if there is no puddles?

PS... it's code 49 on the climate display for non adjusted temp.

 

[madvw]

thick white smoke. Think you've found out already where the coolant is going. Think about it, if theres no water underneath the car...

It has to be either warped/cracked head/gasket or a cracked turbo water jacket.

Who did the investigation? What tests did they do? Sounds like they're trying to get out of a potentially expensive repair to me. The longer it carries on overheating, the greater the chance of terminal damage.

Tbh, if they'e refusing to admit there's a problem (and make sure you have documented proof that they say there isn't a problem) - let it overheat and break. They can't argue if it rolls back to them on a low-loader.

 

[Nigma]

If the fans are not cutting in, check the fuse and fuse socket for the fan. This is the first fuse on the left (There should be two others) located on top of the battery. Its is quiet common for the terminals to oxidise causing the voltage to arc and slowly destory the fuse leg and the socket. I've had this happen to me in my A3 about a month ago, Had to replace the battery cover box.
This could be the cause of it over heating, but by the sounds of it, there is other possible damage as a result.

 

[myrichdad]

Ok - I was absolutely convinced that it was the head gaskett. BUT Audi independant (allegedly ) report said definatley not and I spoke to the bloke and he also said definately not no way. When Mackenzines had it, I told them the whole 8 month long saga and told them my worst fear was head gaskett. they replaced the water pump under warranty - which they didn't need to do if it wasn't broken - and had no liability on it being head gaskett so could have done that if they'd wanted to - but again said no way is it the head gaskett. so.....

what is the tubo water jacket and where can i find it....so i can have a look see if any steam or anything is coming out of there....

Also how do i get the aircon to display a point where i cna put in code 49?

thanks for your help guys - really appreciate it.

Kev.

 

[myrichdad]

If the fans are not cutting in, check the fuse and fuse socket for the fan. This is the first fuse on the left (There should be two others) located on top of the battery. Its is quiet common for the terminals to oxidise causing the voltage to arc and slowly destory the fuse leg and the socket. I've had this happen to me in my A3 about a month ago, Had to replace the battery cover box.
This could be the cause of it over heating, but by the sounds of it, there is other possible damage as a result.

fuses seam fine - other damage as a result ... don't get me started

 

[myrichdad]

ok got this - to acces codes - going to try now.

code appears to be 51?

 

[god_thats_quick]

on my car (can be dependant on age) it's 49 for accurate and 51 for average (should read 90) you just press both the recirculate button and the button at the top at the same time then scroll through using the temp keys.

 

[myrichdad]

Quick update....

Found the codes as described you were right 49 is actual, 51 is ****** smoothed version that basically goes up to 90 and stays there..

Replaced black temp sensor with updated green version. from gsf. 22 quid and fitted from instructions on tt-forum (a-s down :-( boo)

temp controls a bit better up to the point of melt down so i think it's done some good.....watching 49c before and after change - before seemed more variable..

but can't see leak and it's still happening. Also fans definately not kicking in when overheating so.....

Next step - replace thermostat and check they cut in.

Does anyone know the temps they should cut in and out at - so I can watch 49c?? Why aren't they controlled by that temp and not thermostat?

Has anyone done this job? stats are only about 10 quid i think.

Next step after that

Seal up type product to fill small holes?? what do you reckon?

All helpful so far lads - really appreciate this. Want my car back in proper order...

Kev.

 

[myrichdad]

Any comments..

does the seal up type stuff work....

is the thermostat the right way to go...

help.

ta.

Kev.

 

[god_thats_quick]

What temps is your car getting to on code 49?

Are you actually getting loads of steam coming out from under the bonnet or is the water just disappearing?

 

[dummi]

the fan system has a big control module on my a6 controlling % speed of fan according to temperature senders in the radiator. and a second one temp sender in the back of the engine.. the thermostat will release water into the rad once you have achieved minimum running temperature. fans module will maintain max temp.

do a compression test done in each cylinder, refer to a workshop manual for proceedure and expected pressures.

water jackets are in the cylinder block they are the cooling system for the block. if it were me i would next take of the head and check as above if there were warping, headgasket, cylinder block.

mackenzies have been good to me in the past, do as above and get proof in writing

 

[myrichdad]

Thanks for all your help guys.

In answer to questions - on 49c it appears to run between 90 and 110 but has topped out at 121 when actually the dash gauge has moved too and overheating is about to take place.

steam appears to only be coming from around the expansion/filler bottle so i am assuming that is the pressure release over anything else.

Had a quick look today with my brother-in-law and when he took off the oil filler cap there was yellowy gunk on the inside. I must confess I had only checked the water expansion bottlew and the dipstick for this so it may have been there a while but I am guessing it has appeared after Audi and Mackenzies have had it.

Still certain fans aren't kicking in aswell though....

diagnosis - head gasket and thermostat knackered.
action plan - get the stat replaced and then try this seal up stuff from the inside out....see how it works....
then strip head off and replace the gaskett. has anyone done this job, I am pretty sick of donating my cash to audi at the mo.....

have a mate of a mate who will help me, but i'd like to roughly know what i am looking at....so if any descriptions on here or elsewhere you could refer me to i'd be grateful

ta. :-(

sad kev.

 

[god_thats_quick]

Oh dear, sorry to hear all that, I'd say anything over 110 is getting hot, you've probably knackered the head gasket through the heat, but you need to make sure that you haven't warped the head in the process.

I would stop driving the car (if you haven't already) as emulsion for oil will not be doing any good at all to the rest of the engine. You need to get the gasket sorted and the oil and coolant changed along with the thermostat if you think that's the problem. Again if it were me I'd not start the car again until that had been done.

I think it's a pretty big job on an S3 to get the head off however I'm sure if you have a handy mate and are willing it will be possible. Good luck and let us know how you get on.

PS... If it were me I'd be looking to get the car to a specalist as soon as possible - one with a good reputation and a low labour rate.

 

[bantam1]

PS... If it were me I'd be looking to get the car to a specalist as soon as possible - one with a good reputation and a low labour rate.

You could try Midland VW in Cannock as they have been great with my S3. I've used Mackenzies once for a service and they managed to put the wrong oil in and then tried to charge me for the right stuff! That is my only experience and it may have been a one off - but I've never been back to see.

If you want a cheap and reliable second opinion ring Midland VW and ask to speak to Jody.

Cheers,

B.

 

[myrichdad]

Ok, First of all I definately wasn't slagging MAckenzies they have been great. I could slag off the insurance company repairers who have been worse that ****...but it doesn't achieve much does it.

Anyway on to the business

First - replaced the thermostat - drained system down ok, bottom bolt is a bitch to get onto, but eventually got it off and took out thermostatn and put in new one. bottom one still a bitch and have lost an allen k3ey in the engine bay at present. car on stands so can't rock it or bouce suspension to try to find it - definately can't see it! oh well.

Tested old thermostat -it works - oh ****

Then flushed system through to get all coolant out and refilled wiith water

ran up to temp (still no fans)

at 95 degs put the seal up stuff in....

within a few minutes the smoke had completely gone.

I was ****** amazed. check out www.kalimex.co.uk

so then you have to leave it running for 20 minutes while it does it stuff.

Left it running for 40 mins. by the end of which the fans are also cutting in and out like they should. 49c showing between 90 something and 108 max.

left it to cool - drained the system again. now to leave to "cure" for 4 - 12 hours. refill and test.

I think i'll just put water in tommoz to test - just in case it needs another treatment or something. not sure if water level dropped or not in first 20 mins of run.

then coolant change and oil change. has anyone done an engine flush. is it worth it?

then get booked in for normal service which is due soon.

Waddaya reckon'?

 

[madvw]

sounds like its fixed for a few months. Time to trade it in or get the real problem sorted.

 

[Nigma]

Earn Extra Cash. Call 0800 083 3473 or Click www.4yourfreepack.com

Are you a pimp?