2004 Nissan Maxima 6 cyl Front Wheel Drive Automatic 112000 miles
The heater blows hot air as long as the RPM's are above 1500. Once below at a stoplight or in traffic the heater only blws cold air. The temperature gauge is normal doesn't go up or down. Once I begin to increase RPM's the heater will begin to blow hot air again. At the same time there is a gurgling sound when I start to accelerate and the hot air will then start. I went to a dealer and they said it is a head gasket due to exhaust gases backing into the coolant. I wasn't convinced and I didn't want to spend the money on a head gasket repair if it was something else easier to repair. Any ideas?
A head gasket will be evident on most vehicles by severely overheating the engine or by bubbling the overflow for the radiator till it looks like a cup of boiling water in a microwave. Check to see if the heater hoses have a vacuum switch on them if so check the vacuum hoses on the switch to where they go or look under the dash behind the glove box to see if the switches on the dash are moving the one of four electrical switches that control all of the vents