Hi Guys,

wonder if you have any advice on my broken MY02 WRX .......

Symptoms
========

Over the last few days (following a service):
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- great difficulty in de-misting the passenger-side windscreen (not my side)

Starting yesterday:
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- engine overheating under gentle driving conditions (water temp gauge in the red zone, climbs quickly while I watch it)
- no hot air from either air con, or just the heater (blows cold air)
- loads and loads of smelly white water vapour through the vents into the cabin (could this be coolant ??!)
- sometimes (just sometimes), there is a burst of warm air (and more vapour), however when this happens I can't actually then get any cold air ! ie. I've lost control of temperature altogether in the cabin
- very low coolant levels in the rad expansion tank (I've topped this up twice)


Needless to say, I'm most worried about the engine overheating, but I'm also slowly gassing myself in the cabin trying to work out what is going on. Other than the above symptoms, the car is running like a dream (full boost, normal oil pressure) - until it overheats of course.

Any ideas?

I can't see any burst pipes, the radiator looks intact (but how can you tell) .......

I've already used the 'search' function for 'white vapour', 'radiator', 'air con', 'overheating', 'heater matrix' etc........

Trouble is I can't get to a dealership as they're all closed over this holiday period!

Was planning to head up to the Lakes over the next few days as well, grrr.

hope you can help

cheers
DaveR

 

I'm no expert Dave but something similar happened to an old volvo I used to run, sounds very much like there is little or no coolant in the system from the symptoms you mention, especially the fast rising temp gauge and abscence of heat from heater. As for the white vapour... no idea sorry.. (Aircon coolant?)

Cheers
paul

 

Maybe the fault lies in the heater core.

Check the front footwells to see if they are damp/wet. If yes, probably heater leak.
Does the vapour have a spicey smell to it? If yes, probably heater leak.

You would need to get a pressure test done on your cooling system, this will show if you have any leaks.

Many smaller workshops would have a pressure tester, might be worth a look through Yellow Pages to see if anyone's open today.

Big-G

 

thanks for the advice guys, I'll go and have a look for leaks

any one else with any more info/ideas, this would also be appreciated

 

Definately sounds like the heater matrix has gone to me.

 

Yeah sounds like heater mayrix to me aswell had one go on an old renault 25 I had (It had lasted 14yrs before it went). Get it to the dealer and changed under warrenty. They shouldn't really go after 2 1/2 yrs.


Jase.

 

DaveR, I'm sure there are a few dealers open, or at least they will be tomorrow. Gatwick Subaru wanted me to go up tomorrow to have something done on my car.
How about getting Subaru assist to recover the car?

 

Yep I would go with heater matrix as well

 

What does it smell like?

Coolant has a sweetish smell - if that's what your smelling through the vents - almost certainly heater matrix.

You may not get wet footwell carpets as the heater box has a drain pipe for the a/c condensate to drain out.

 

Thanks very much for all the responses guys --> yes the smell is a sweetish one so it's probably coolant (and a broken heater matrix), as you say.

I'll go and argue it out with the dealerships tomorrow then.

Damn and blast ......

thanks again
DaveR

 

no wet carpets

how would a broken heater matrix be related to the fact that the car is overheating though ?? --> doesn't the heater matrix just control air con and heating? or it it linked to the engine temp as well?

 

Well if you have a leak, you loose coolant. Lost coolant is replaced with air.

Air in the system causes all sorts of wierd happenings, such intermittant overheating, intermittant or no heater output, Or in the worst case: overheating when the temperature guage reads normal.

The heater matrix uses engine coolant to heat the interior cabin, so it's directly linked to the engine temperature.

 

ah, right, that makes sense now then.

thanks for the info

cheers
DaveR

 

This is the bit that would worry me.Was all ok before the service? Steady coolant level with no regular top ups needed.

Was it the service where they drain & replace the engine coolant?

Could be they left air trapped in the system if they rushed the refill or a pipe may have not sealed properly after being disturbed.

Either way the garage should put it right for you.Inspecting the Cooling system,Hoses and Connections is number 6 on the service check list & is done on every service.

Mark

 

Cheers for the info Flat Eric.

The car is in the dealership now and they've confirmed there was a pinhole in the heater matrix, which is being replaced under warranty (unfortunately there will be a delay however while they get clearance from Subaru Benelux - as it's a European car).

I agree though about the 'following a service' point - the car was definitely playing up the moment I drove off from the service, but for some reason I didn't put the factors together. Maybe there was a combination of a new hole in the heater matrix AND air in the system --> I say this because there WAS a running/gurgling water noise audible from behind the dash (but this has been present to a greater or lesser extent since the car was new and has caused no other problems in 50K so I thought nothing of it).

cheers
Dave

 

This is because cars with aircon have a drain tube in the bottom of the heater box to let out any condensation, and this has the added bonus of letting out leaking coolent so it dosent ruin your carpets.

 

Did you have a cam belt change by any chance, if so I bet they forgot to plug the rad fans back in leading to the damage.

as a thought

bob

 

Hi Bob, thanks for the suggestion but no, it was just an 'intermediate service' - I went there specially early mid service interval to prep the car for a planned trip up in the Lakes