Audi TT 225bhp - 2000 over heating

[BeasTT]

Hi new to the forum. was wondering if anyone can help. I have a TT year 2000 225bhp which has started over heating. its done 97K miles. Temp gauge went up to 115 whist in traffic. I managed to get the temp down by turning the heater on - but then the needle dropped to 60. its been dropping to 60 for a while but never gone up to 115 before.
before the start of this fluctuating temperature it was stable at 90.

Checked the coolent over flow container this morning whilst it was cold and the coolent was way above max level. could this be affecting the pressure in the cooling system.

Also i havent actually seen the rad fans (either of them) kick in at any stage. but i havent checked when the car is over heating as it has not been possible. how could i test the fans?

appreciate any guidence you can offer.

[Crasher]

Three common possibilities. The gauge is lying, I often see TT’s displaying 115°c but when the temperature is checked with a diagnostic computer viewing the live data from the instruments, it says around 95°c. Also, putting the gauges into outputs test with the diagnostic system should have the fuel gauge and temp gauge both reading half way, I would expect the temp gauge to say 115°c then as well if it is the fault I think you have. A fault code read would possibly show a coolant temp sender fault with the way it dips down. The other possibility is the water pump has failed butt if the heater is producing hot air I would not think it is the pump. If the pump fails, the fans won’t run as water don’t get to the radiator easily. If it was realty 115°c, it would boil over so I think it is lying. Get it checked ASAP to be sure.

[BeasTT]

Thanks Crasher. I had the cambelt service done about 12 months or so ago and water pump was changed then.

i assume only specialists or dealers can conduct the testing?


does anuone know of any decent specialists in high wycombe (buckinbghamshire)

[kite]

You can check actual engine temp. with the climate control. 49c is the one

http://www.wak-tt.com/climate/climatecodes.htm

[Crasher]

Or someone who has suitable equipment and knows how to use it.

[kite]

Or someone who has suitable equipment and knows how to use it.
I was just trying to help someone who may not have access to VCDS !

[Crasher]

I didn't say you weren’t, I was answering his question as to whether he had to go to a dealer or VAG specialist, in that a normal garage could do it if they possessed suitable equipment and knowledge. At that point I had not even seen your reply as I wrote my reply in Word from the email notification, having a bad day? Chill out dude!

[kite]

I'm cool :D

[BeasTT]

Thanks for the advice guys. I'll check via the climate control and see what comes up. i checked again yesterday it wasnt showing much over 90 but when i opened the coolant reservoir tank it bubbled a little.

thanks again for your help

[Crasher]

That seems more like a faulty coolant temperature sender, have the engine and dash scanned for fault codes but I would replace the sensor anyway, sometimes they don’t come up as faulty even when they are. The coolant system should bubble when released, it is a pressurised system.

[BeasTT]

how do i change the coolant temp sender? is there a guide anywhere on the www.?

i checked temp with climate control
cold 49C = 30 deg
hot 49C = 67-75
The temp displayed on the climate control varied but remained in harmony with that shown on the gauge.


The link to the climate control codes also states 51C to be the Engine Coolant temp. I check this too.

cold 51C = 23deg
hot 51C = 90deg - this remained constant through out my journey


not sure if this clarifies anything?

is diagnostics done with VAG-COM as i can get hold of the software and cable.?

[kite]

"how to"

http://www.wak-tt.com/tempsensor/tempsensor.htm

I would change the temp. sensor, if that don't fix it change the thermostat

[BeasTT]

thanks for the link. will try this tomorrow.

just for clarity is it 49C or 51C that i am checking or is it both?

sometimes the temp needle doesnt move but can start working again anytime. this is intermittent however it happened today and (as i now know how to check via Climate control :beerchug:) 49C = 121degC whilst car was cold!!! when the needle started moving the display on the climate control corrected it self and rose to 72deg along with it.


I also scanned for engine and dash fault codes and these came up

2 Faults Found:
16396 - Bank 1: Camshaft A (Intake): Advance Setpoint not Reached (Over-Retarded)
P0012 - 35-10 - - - Intermittent
17608 - Boost Pressure Control Valve (N249): Mechanical Malfunction
P1200 - 35-10 - - - Intermittent

does this help or does this tell me i have even more problems :(

When monitoring the realtime VAGCOM data, the temp was showing 72deg. This was whilst the temp needle was still resting and the Climate control stilled errored (49C=121deg). 51C was as usual showing 90deg.

i will change the suggested sensor but just wondering if this will cure the dip in temp and bring it back to 90deg. or has this confirmed my thermostat needs changing too?
Sorry for loads of questions.

[kite]

Change the sensor.
Clear the faults and see if they come back.
49c is actual engine temp.

[Crasher]

Yes you have more problems. 17608 is normally just a dirty throttle body but 16396 means you have to fit a new cam timing unit and that is cams out.

[BeasTT]

changed sensor and the needle didnt move for a while then shot off to over 100. 49C=104, then dropped to 72, eventually for the last 10 minutes drive, 49C averaged 98deg going up to 100deg at times ( I assume this is too high?). The needle stays on 90deg.

I dont know if the results are conclusive so i'll see what happens in the next few weeks.

i cleared the codes and all cleared except:

16396 - Bank 1: Camshaft - reappeared a couple of times but now cleared

00849 - S-contact at Ignition/Starter Switch (D)
31-00 - Open or Short to Ground


ill keep a check on these.

[BeasTT]

hi me again, just ran another scan and now only get the following codes:

Address 08 -------------------------------------------------------

1 Fault Found:
00604 - Potentiometer Positioning Motor for Air Flow Flap (G113)
30-10 - Open or Short to B+ - Intermittent


Address 35 -------------------------------------------------------
1 Fault Found:
00849 - S-contact at Ignition/Starter Switch (D)
31-00 - Open or Short to Ground

gonna surf for some info on this but thought id keep you guys in the loop as not sure if these possibly relate to my problem.

I also checked the temp again via climate ontrol and 49C=53deg on cold start (looks better) but started to increase and went to 60deg with ignition on but engine not running....is the increase temp normal without engine running??

will take it for a good run tomorrow and look up these codes again

appreciate if you have any further thoughts. thanks for your help

[kite]

When the engine is running the temp. should go to around 97c then the fans will
cut in and the temp. will drop to around 88c, you will se the temps move between the 2.
if the engine runs cooler then the stat could be ******.

[BeasTT]

thanks Kite.

ill monitor it and see how it goes.

one quick question for Crasher et al. you mentioned Output test the coolant and engine temp, but i cant find the section that displays this in the diagnostics software. i am using VAG-COM v311.2

if you can point me in the right direction that would be great.

[BeasTT]

just to close this off: Thermostat changed and this has corrected the problem. car running sweet at 91deg. 49C code really has helped. still use it when ever i get in the car as good to monitor.

thanks for all your help guys.

[BeasTT]

Hi, the overheating problem seems to be back, the car was running OK since the thermostat and temp sensor change, but now im really confused as to whats happening.

On my way home 49C = 107deg this more or less remained consistant through out my journey which was motorway and local driving for 45 min.

when i got home 49C went as high as 111deg . I connected the VagCom and Coolant Temp showed 90deg.

so now this VAG com reading is contradicting the 49C reading.... :(


The rad fans are working but not sure at what stage they kick in. With the rad fans on, 49C stilled =107 deg

the heater works so i guess that confirms the waterpump is working,

can some one advise me on the next troubleshooting steps as im a little stuck not knowing what to do.


any direction provided will be greatefully received as i really need the car to get to work and im worried the next trip might overheat it into Red. :mad:

[BeasTT]

to add to my comments above these were the faults which i have now cleared

16396 - Bank 1: Camshaft A (Intake): Advance Setpoint not Reached (Over-Retarded)
P0012 - 35-10 - - - Intermittent

and

00604 - Potentiometer Positioning Motor for Air Flow Flap (G113)
30-10 - Open or Short to B+ - Intermittent


00849 - S-contact at Ignition/Starter Switch (D)
31-00 - Open or Short to Ground



could any of the above be causing the car to play up?

[Crasher]

Sounds to me as though the dash is going faulty, I pulled one out today to send for repair. It was reading 110 degrees centigrade but VAG-COM showed 90.

[kite]

If the dashpod is broken, Audi will change them FOC.......

[Crasher]

My dealer won't on one as old as this, it is a 2000 model. We checked with them and they weren’t interested.

[BeasTT]

thanks for all your input guys but one question...if 49C is showing same temp as the pod does that still point to a faulty pod? it went up to 115 today and i turned back and parked it up. :( had to get lift into work as didnt want to risk it :(

to confirm does Vag Com measuring block 01 "Coolant temp" represent the engine temp? so when i read 90deg is that the actual engine temp?

i also get the thermometer / coolant warning light coming on when i first start the car andthen this goes off. this has occured occationaly since i bought the car but its now consistent each time i use the car. it goes off though after a minute or two.


sorry for sound a little silly but i thought i got all this sussed and now feeling gutted :(

any further guidence appreciated as i really need car to get to work.

thanks

[Crasher]

Yes that engine block 1 is showing engine temp as seen by the ECU, you did change the coolant temp sender didn't you?

[BeasTT]

Hi Crasher, yes i change the sensor (bought from dealership) and then the Engine Block 1 was showing 75deg. I then changed thermostat and it became ran at 90deg. at that stage VAG COM and 49C (and temp gauge) were all in sync. the car was running sweet.

When i bought the car (5 years ago) the pod sometimes worked and sometimes didnt . and when you guys told me about 49C this showed 121deg when the temp gauge did not move. however since the temp sensor and t-stat were changed 49C has only shown 121deg once i.e temp gauge did not move either).

the "overheating" only started again on Monday when i hit traffic.

this morning it shot off to 90 deg within 5 min and i only got down to the end of my road. its never "warmed up" that quickly and VAG COM showed 25deg.

49C stayed on 90 for a short while and as i started accelerating (3000 revs 5th gear) it started to increase. it fluctuates between 103 - 107 and sometimes comes back to 90 then back up again.

[Crasher]

Sounds like the water pump impeller may have failed.

[BeasTT]

water pump was changed a couple of years ago when the cambelt was changed. i guess it would be out of warranty now?
which water pump do you recommend as i understand there are ones with plastic impellers and ones with metal.??? is it worth changing the cambelt and tensioner (??) too as something squeaks on first start for a minute or so and then quitens down.

[Crasher]

I have stopped using the metal impeller aftermarket pumps and I only use genuine VAG exchange pumps. The plastic impellers to me are not an issue (they are used for a good reason but not one really applicable in our temperate climate) and I like the two year warranty on genuine pumps. The cam belt and tensioner must be changed again and I would also recommend a genuine belt kit. I worry about my diagnosis of a pump though if it is only a few years old, it makes me think more of a stuck closed thermostat as I have noticed you say the heater gets hot.

It sounds like your V belt tensioner is noisy, I must do mine as it is the same and making the same twittering noise when cold, I just haven’t had the time to do it.

[BeasTT]

thanks crasher. i got the cambelt changed from Audi specialists so i'd guess they would have used genuine parts.


i bought the thermostat from Europarts.

if the Engine block remains at 90deg is it OK to drive the car regardless if 49C and temp gauge are showing high readings?

[BeasTT]

just did some more diagnostics ..but not sure if it helps or hinders.

confirmed heating is fine. from all air vents.

drove car at 30miles temp stayed at 90
drove at 40 and started to overheat.
did not kick it into turbo, kept revs low 2000 -3000

parked up after a good drive and 49C showing 106deg.
checked fans and neither working (engine running and heating on.
turned engine off fans remained off.
restarted car. fans kicked in immediately
turned off heating and both fans stopped. 49C still showing around 106
turned heating on and both fans kicked in. turned off again and both fans stopped.

checked pipes to rad.
it was dark so not sure which ones i should be checking.
there are three pipes at the front, two going to left side - one v. warm, one cold. thirdpipe going to right (goes to coolant temp sender.) which was v. warm

not totally familar with how rad fans supposed to work so not sure if this has anything to do with my problem, any further advise appreciated.

is there any further tests i can do to confirm the actual fault

[Crasher]

If the fans only come on with A/C Auto then the fans or fan controller are faulty, I change a lot of cooling fans.

[BeasTT]

thanks Crashed. do you think thisis the cause then? shall i start here? any particular method to use? as i'm just doing trial and error approach.

[BeasTT]

sorry i meant to say "crasher"

[Crasher]

Crashed, Crusher-all good with me :D. Disconnect the cooling fan switch plug on the radiator (a complete **** to get at and squeeze the retaining clip) check you have power at socket 2 on the red wire and if you do, bridge socket 2 to 1 on the red/white and the fans should kick in ignition off and to socket 3 they should run ignition on.

[BeasTT]

cheers crasher, i'll try this tomorrow. fingers crossed.

[BeasTT]

Hi Crasher. its been so cold that i havent had a chance to look at the car.
as im snowed in today i thought id search for the cooling fan switch plug on the radiator but finding it difficult to see from the top.

do you have any pics as to the exact location. is disembling easier from above or below?

also dont know if this helps but the cars been parked up since we last spoke. its been a pretty cold week and as soon as i started the car today both the fans kicked in immedately. The fans continued to run with heating on or off.

49C=121deg (on cold start). shall i continue with testing the cooling fan switch or does this tell you anything else.

im going to try and see if i can sort today so appreciate if you stay on line with me pls:1zhelp: thanks for your help to date (and everyone else in the thred)

[Crasher]

It is on the left of the car just below the level of the headlight and the battery. I tried to take a pic on the one I am just working on (air bag ECU) and I can’t see it.

[BeasTT]

is it screwed in or just a retaining clip? will i lose water once removed? im going to give it a bash but just want to be prepared for the worse.

[Crasher]

It is screwed into the radiator and I use a very deep reach 30-mm six sided socket which only just lets you remove it. I did one on an Octavia VRS the other day (almost identical) and that was extremely awkward to get at from above and you can see it, the one on yours is accessed from below and is quite difficult to get at. Audi quote just under an hour which is a bit optimistic, I would say just over an hour. Yes you will get covered in coolant so engine cold and release the pressure by removing the expansion cap.

[BeasTT]

but at this stage do you want me to just remove the connection and test.
so i dont need to take this off (yet) right?

[Crasher]

Yes, sorry-just to test.

[BeasTT]

Hi crasher,
just to let you know ( and anyone else interested in my progress :( )

- sorry for detailed blah blah blah but question at end

i doubled checked cooling fans before attempting to disconnect as you suggested as i found my diagnostic method to be wrong....

With Climate Control set to LOW, and enabling Recirculation the fans stopped as expected.

I then heated up car on idle until the fans kicked in at Engine temp around 98deg and then went off once temp fell below. Engine Temp did not go over 100. This was consistant. As i was previously testing with the heaters on etc (and sometime off) my results were never conclusive. :banghead:

so as things stand when the temp gauge does not move, 49C = 121deg
I understand this is default when there is a problem and the fans kick in because the car recognises there is a problem somewhere and to be on the safe side it runs the fans (which is better than letting the engine overheat.)

Also when the car "overheats" according to the temp gauge , 49C increases until it shows 121deg and fans kick in again.

During this time VAG COM continues to show engine temp at 90deg, so i'm confident the car is actually fine as you origianlly suggested and the pod-dash is at fault.

I have booked the car with Audi dealer on Friday to investigate the faulty dashpod. One dealer has advised that as the car does not have a Full AUDI Service History Audi will NOT change for free. the dealer i have booked with, said similar but said Audi MAY make (and i believe have occasiionally made) an exception. so i dont think it is down to the year of manufacture.

So the question is really has anyone heard the same or has anyone had one changed for free and not had a F-AUDI-SH. Im hoping to get mine for free but want to take as much ammunition in with me :swordfighshould i hear the worst (quoted over a £1000 if i end up paying for it...and i will have to get it fixed no matter what the outcome :(

[kite]

Here is a link to a letter from Audi UK to a TT forum member
confirming that Audi will replace faulty dashpods on any TT

http://www.tt-forum.co.uk/forum/viewtopic.php?f=2&t=124238&p=1300241#p1300241

[BeasTT]

Kite you star!! :beerchug: nice one. will print this off and take it with me. hopefully there wont be any arguments. Oxford Audi point blank said AUDI wont change unless FAudiSH . Amersham AUDI said same but said AUDI will considere each case but cant guarentee FOC. This letter should hopefully make them see the light.

thanks again for all your support on this forum guys. Respect! and keep up the good work :D

[BeasTT]

So..... what happend next......???

Well it was good news for me. Audi changed my dashpod free of charge as good will http://www.vwaudiforum.co.uk/forum/images/icons/icon7.gif

I asked if i could pay £1 plus VAT for warranty of the replacement, but was advised that as it was replaced with Good Will I was not eligable....( where the customer has had to pay for the replacement then Audi do accept the £1 plus VAT)

Dont know if this helped but I also contacted AUDI UK Customer Service (google for the number) advising them of the contradicting information i was receiving from different dealerships. they advised thye could not comment until i hand the car in for diagnostics and they would take it from there. I was also advised to take in my V5 form so my details could be logged with Audi UK.


I did receive a call from Oxford Audi who clarified that Audi has refused someone as they did not have a Full Audi Service History but each case is dealt with individualy. now i'm not sure why thye decided i warranted good will but apparently they take various things into consideration i.e time you have had the car, if you ever used the dealership in that time, year , milage, have they already replaced this by good will (for me or for previous owners) etc. but I THINK the main one is have you ever used the dealership for general work...which i have done in the past on work that i only trusted Audi dealership to do or i was naive at the start and handed it in for servicing...so i had some Audi Service History.

So I think each case is individual but it helps to get all you amo together so they know what you are talking about...and i was ready for a battle with "Kites" letter in my pocket ....but glad to say i didnt have to go down that path.

so thanks Crasher and Kite for all your help - top guys. :beerchug:

lets hope the one they put in doesnt go faulty as i think i'll be paying for the next one! ..unless it becomes faulty very very soon

[BeasTT]

just to add ...

car manufactured Dec 2000

Milage 99971

previous owners: TWO