Overheating AND No heater!! HELP

[tyrrelll]

Hi guys, so the A3 passed the MOT last week but now its given up on me.
I started it from cold earlier, 10 mins later the temperature is MAX so I immediately stop, let it cool and start it again.. 5mins later its overheated again...

Waters fine and driving fine BUT the heater no longer blows hot air? Could it be the water pump? Any ideas? I have the mechanical knowledge of a brick.

 

[Turbo jay]

If its over heating it could be the waterpump best thing too do is get it scanned via VCDS or a local garage,but I wouldn't be driving it far and letting the temp go over 90 could blow the gaskets.

 

[Ironborn]

Unlucky agree ^ should be the waterpump. Is it a diesel or petrol because 10 mins seems a bit quick. When mine did this I could drive up to 7-10 miles before overheating. If your going to drive it, drive with the heater fans on full blow it helps alot

 

[BlueSpark]

I agree that it may be the waterpump, but i would also check first that you havnt just got a airlock in the system. The worst case senario is that the head gasket has gone. As advised by other i wouldnt drive far it as you could damage it further.

 

[JudderMan]

There seems a lot of this at the moment, any reason or is it just the cold temperatures? I'm always careful and let the engine heat up before taking it over 2k/rpm but what are these MOT testers doing?? Mine was ragged to death by them and they complained that my car was filling the garage up with smoke. Some pooh in an envelope is heading their way soon.

OP - Get a hydrocarbon test on the coolant to see if it's mixing. If so, then it's head gasket time.

 

[eddyd]

Could also be a thermostat stuck closed.
Is the radiator cold when the engine is overheating?

 

[peeved]

Things it could be

• Blocked heater matrix.
• Stupid plastic water pump, take off hose to thermostat flange and have someone crank the engine over to see it is pumping.
• The metal piping on the overflow return
• A blocked radiator
• Any one of the pipes
• System airlocking because of cracked head/cylinder liner or blown head
• Faulty thermostat

I'm offering this but have yet to solve my own problems! My personal opinion is once the waterpump goes the first time it screws up the engine for the rest of its natural! I have recurring problems with overheating on my A3 and I have replaced practically every component in the cooling system!!

 

[klik]

Could also be a thermostat stuck closed.
Is the radiator cold when the engine is overheating?

+1

 

[MrLapou]

Go for air lock or stuck stat.
Easy to tell by touching the hoses to see what's hot and what's not.

 

[tyrrelll]

Thanks for the replies guys! Finally got it sorted. Turned out to be the waterpump! Seems to be common, I had the same problem with my old 8L. Guess the silver lining is that it was a good chance to replace the cambelt as well.