Heater Problems

#1

I have a 1997 Nissan Quest and the last several times I started the engine, a strange smell occured (like burning rubber. The last time I started the smell was more intense than the others. After driving for 10 miles, the heater continued to blow cold air no matter temperature setting. I am on a return trip to my home state 1200 miles away. What could possibly be the problem?

#2

What is the termperature gage (or idiot light if so equipped) doing? Is the coolant level OK, not just in the plastic reservoir but in the radiator as well? DO NOT REMOVE THE RADIATOR CAP WHLIE THE ENGINE IS HOT. Is your serpentine belt that turns the water pump (and everything else under the hood) intact? If a bearing froze up, (idler, alternator, water pump, power steering pump) that will turn the belt into burning rubber in short order. That would account for the smell. If the belt is broken and/or not turning everything it should, SHUT IT OFF NOW. Driving it while it’s hot will ruin the engine in short order.

#3

Thanks, the engine temperature is running cold and the belts seem intact. I do have a small leak in my power steering, but it has not affected the steering. Nothing seems to be frozen from what I can visually observe. The engine starts on a dime and is running smoothe, just no heat. The burinig rubber smell occured again this morning when I started the car but is soon dissipated. I thought it could be something simnple, but it must be more complicated. It is New Years Day and every dealership is closed!

#4

If the engine is running cold, the problem might be with a thermostat that’s stuck open. This would explain why there’s also no heat from the vent system.

Tester

#5

Happy new year to you. I hope you will make just fine on your trip. Could you please follow the heater hoses and see if you can find a valve with a vacuum tube on it ?
Make sure that that vacuum line is without any cuts or broken, otherwise you will have no heat. Hope this helps. This drawings may help you:


this is a pic of the valve at the firewall:

#6

Thank you so much. The links to the illustrations were perfect! Happy New Year.