2001 Honda Civic
A few weeks ago, the heat on my heater would only work when I was driving the car, cold air would come out when the car was idle.

I then read up to turn on the car, remove radiator cap, rev the engine to 2500 rpm, turn the heater on half way for a few mins, it worked but the problem has came back up again.

I got the dealer to do a air pressure test and they said its the head gasket, $1300. I dont have any visible coolant leak and engine temperature is fine.

Anyone got any suggestions on what I should do.

Thanks,

 

I have a '96 civic EX....similar condition but what nailed down the bad head gasket for me was a cooling system pressure test. Held pressure OK with no leakdown (17 psi). With spark plugs removed and cranking engine, no pressure buildup in the cooling system. Put the plugs in, crank the motor and wow! Instant 25 psi in the cooling system! Removal of the valve cover showed the nice milky brown coating for icing on the cake.

 

not sure what you exactly mean, are you saying its just bad spark plugs ?

 

no, he was describing the pressure test. Hes agreeing with the dealers diagnosis

 

I would attempt it yourself before paying $1300. I did my first head gasket at 16 years old and only cost me ~$100-150. Do some searching on the process.

 

I second that... The good thing about I4s, is that you can pull the head without pulling the engine