no heat on idle after 5 mins

[atweats]

Hi all , just purchased wr1 number 376. didnt notice at the time of sale but once i got her home the heaters start to blow cold when left on idle for 5 mins or longer . It doesnt over heat in traffic and heater are hot as hell when revs are picked up over 2k . Havent had too much time to look over her yet due to the snow ect but have been told possible sticky themo stat or low on water ? Checked expansion tank and res tank but seem be spot on .

Any suggestions ?

Also feels like iv got a sticky throttle cable some days or a heavy foot problem perhaps . Im used to driving a drive by wire vw so it may just be me. throttle feels hard to press especially when cold .

[WR 1mposter]

Possible air lock in the coolant system !

Try taking off the expansion cap and leave running for a while see if it will bleed thru !

[marchar]

hi and welcome, as imposter suggests leave the expansion cap off for about five-ten mins on idle, thermostat can't be sticky as its getting up to temp? Maybe a water pump problem, has the pump been changed/any signs of a leak in that area?

[SteveS]

Defo sounds like a cooling problem, pump, belt, stat or collapsed hose, hope you get it sorted sooner.

[Ant]

It could be the extreem cold, at idle because of the freezing air going through the heater your taking more heat out than is being produced, this will lead to the engine going cold, this happens in my rac van when parked up waiting for my next job, you pull up with temp on normal but after 10 mins of idle with heater blowing hot the temp gauge starts to gradually drops towards cold if its very cold out there, it likely you have nothing wrong with your car.

And just to add if you start bu99ering around with it you may end up with a problem when you diddnt have one in the first place!! I would wait and see what its like when the weather warms up a bit.

[Steveyk]

It could be the extreem cold, at idle because of the freezing air going through the heater your taking more heat out than is being produced, this will lead to the engine going cold, this happens in my rac van when parked up waiting for my next job, you pull up with temp on normal but after 10 mins of idle with heater blowing hot the temp gauge starts to gradually drops towards cold if its very cold out there, it likely you have nothing wrong with your car.

My VW Caddy does this too, at a standstill you can actually see the water temp guage dropping when you run the heater.

[asperformance]

seems to be a VW issue as i have this with my T5 also, however never had it in the Subaru even last year at -15..........

[marchar]

i cant afford to leave mine running for ten minutes to find out

[atweats]

UPDATE- topped up with coolant at the weekend in expansion tank . seemed to fix the fault of the heaters going cold and started drive normalally ok . then tonight had bit of a blast on the m6 and at lights got steam from under the bonnet smell of antifreeze - not over heated and engine temps still blowing hot air and needle central on engine temp . Looks like the expansion tank caps leaking coolant when the engines under load . Is this common or have i problems elsewhere you think ? . pipes all seem be hot need radiator but cap ontop of radiator is only luke warm.

[Steveyk]

Check the expansion tank (the metal one) filler neck, my old WRX had the same fault, I changed the cap 3 times before I found a tiny crack at the base of the neck. It seeps out under pressure when it's hot.

[atweats]

will check when its light tommorrow . just brough new 1.3 bar cap incase too .

[atweats]

your suggestions seem correct .

Woke this morning to see the filler neck on the header tank cracked 70% way around . looks to have rusted in this area and just got worse >

lucky just managed get one from andyscoobyspares on ebay + new cap.

Only had her a week . hope its just teething problems :/

[Steveyk]

Glad you're sorted mate, I still have the old tank off my WRX, but it's still cracked. I want to get it welded and powder coated red then fit it to my 1.