No heat when idling

[Khalil.e]

Quick question for those in the know:

When idling/at a stop light my car stops blowing warm air, and begins to blow cold air. In addition to this, the car really isn't blowing hot air when it should - just a 'luke warm' air.

Any idea what the problem could be?

*Last year the timing belt/water pump was replaced - could the coolant be the issue?

The car is an '06 Acura TL...

[blitz]

Low coolant or an air bubble in the lines somewhere. Idle the engine with the coolant system open to atmosphere for 5-10 mintues, then top up if necessary.

[J-hop]

Also could be a t-stat, does the car take a long time to get up to temp? Only other thing I can think of is a water pump, but if it was a water pump chances are you'd notice temp fluctuations (ie would probably get really hot in stop and go traffic). My guess out of the two would be a t-stat

[Khalil.e]

hmm...if it was the t-stat, wouldn't it stay cold for a longer period of time?
(No idea, myself)

Blitz - by keeping the cooling system open, are you referring to keeping the radiator cap open?

[AE92_TreunoSC]

Start with coolant level.

[J-hop]

Originally posted by Khalil.e
hmm...if it was the t-stat, wouldn't it stay cold for a longer period of time?
(No idea, myself)

Blitz - by keeping the cooling system open, are you referring to keeping the radiator cap open?

Yea it would stay cold for a long time and you may never get hot air blowing through your vents. He means keeping the overflow/expansion cap off. However I would consult a manual first, this was how you used to do it but my VW service manual does not recommend this, also most t-stats on newer cars can bleed air past them so they will still open and you'll get flow but blitz is right a giant air pocket could give you similar symptoms.

[forced_eg]

check your rad cap pressure to see if thats holding up, check coolant, what color is it? is the vehicle heating up to normal temp? did they put the right stuff in after the t-belt? measure/feel your heater core inlet and outlet temperatures

if all is good then my best guess is an issue with a blockage in your heater core, minimal flow at idle means the heater fan is stripping the heat faster than new coolant can be delivered in, if so then try a backflush (disconnect heater core and apply a garden hose to the outlet) be carefull not to apply too much pressure and cause a leak in your heater core

[Disoblige]

Yep it could be the thermostat. Easy fix if so.. (Happened to me, no warm air when stopped).

Other than that, coolant flush.

[Rat Fink]

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