Overheating and climate control not working

[scruffy_77]

Hi,

I am new to tgese forums, so Hello to everyone.

I wonder if anyone can help, my Audi is driving me crazy now. I have an A4 1.8 T 2004 Limeted Edition. When the car gets going it overheats up to 130 on the dial and the interior heater just blows cold air. The coolent is also boiling when I release pressure from it.

I have changed the thermostat today which I hoped would solve the problem, which unfortunately hasnt made any difference and the car still overheats. I know the water pump is working as I removed the hose from the water intake and water pumped out freely. I assumed at this point it would be the head gasket. I took the car to my local garage which did a test using a device Im unfamiliar with which the liquid changes colur if the head gasket is broken, however after testing it didnt indicate the head gasket, although the mechanic said it does seem like it is the head gasket.

The only other thing I can assume is an Air Lock in the system, however I dont know how to bleed the system as the bleed valve seems to have a plastic stopper in it which I dont want to play around with too much. Also at the garage the mechanic spent some time moving the pipes to try and free anything to no luck.

I am a bit stuck now to what the problem actually is, I have been quoted £1000 for a gasket change, but obviously with the new year and credit crunch i hope that this isnt the route i have to take. I did also call Audi but they wanted 100 an hour just to look at the car, and also I did assume it would just be the thermostat.

If anyone has any ideas or suggestions it would be great and more than helpful, I am at a lost end with the car now, and thinking the worst of a head gasket and an empty bank balance.

Many Thanks

[Issac Hunt]

Could still be the waterpump, your test isnt 100% conclusive. The water pump impeller can still slip/spin on the pump drive shaft at higher RPM's which wont circulate the water around the system.

[scruffy_77]

thanks for your reply , well that is some hope, I am so worried it being the head gasket. The guy at the service desk at my Audi dealer also said he would be very surprised if it was the head gasket due to the age of the car.

Dont know if it makes any difference but if the engine is warm / hot from sitting idle, eventually the water starts boiling and the engine still goes up to 130 on the temp gauge. Would this count out the water pump if the rpm's are just running at engine idle?

[Issac Hunt]

The only way to dscount the water pump is to change it. Its a far more common failure on a 1.8T than the head gasket.

[scruffy_77]

ok, I hope it is that. Out of interest, I changed the thermostat following the Haynes manual, it was fairly hard but possible, do you think changing the water pump would be the same difficulty or would you recommend taking it to the garage to have this job completed? Roughly how much is it to replace it also?

Another note, when we refilled it after the thermostat change, we couldnt get more than 2 litres of coolent in, it didnt seem to want to recirculate around. Not sure if this has any effect the problems it is having.

[scruffy_77]

Hi Mate,

Just wanted to say thanks for your help, I really appreciate it. Replaced the water pump today (getting the car in the service position was quite hard but managed it) And as you said could be the issue, the impeller was smashed in three!! I have replaced now with a pump with a metal impella and all is happy as larry. Really appreciate more than you know, as I mentioned earlier, the garage told me the head gasket because their test prooved that water pump is fine (which it clearly wasnt). So all in all it is a happy new year for me

Thanks Again.