strange heating problem with 1999 chevy malibu

03-23-2011, 07:23 PM

About two weeks ago, my oil light came on. My coolant light had been on for awhile, but I drive an older car and hadn't noticed any issues (mostly heating issues as I am always cold and it is winter), so I didn't top off the coolant until I had to open the hood to deal with my oil anyway. I topped off both oil and coolant and have since had no dashboard lights come on. My engine runs fine, or as fine as it did before either light came on.

About the same time as the oil light came on, I noticed a strange thing start to happen with my heater. I should say with the fan in general because it happens whether the temperature is set to heat or to cool. When I started my car up in the mornings, the fan would work just fine, but if I idled for awhile it would dim and then stop. The longer I drove the car, the more quickly it stopped. It would start again when I started to drive. Then it began to stop when I idled just long enough for a stoplight. It took longer for the fan to start again, but if I drove long enough without stopping, it would.

Lately, the fan only works for the first minute or so that I start my car up in the morning or if I am able to go at least half a mile without braking. It immediately stops when I stop. I have been very cold except on sunny days!

My dad said he thought it sounded like the alternator, and I believed him for awhile, but the car has always stalled once or twice a day when I first start it up. But I can always get the engine to turn over, and upon further observation, it hasn't gotten any worse. Plus, the fan gets better when driving, and from what I've read, if it's the alternator, it should get worse when driving. I haven't had any other problems with electrical systems. I did just change the battery not too long ago, if it has any relevance.

Is this a wiring issue or an issue of needing the fan cleaned and lubricated? Those are my best guesses now, but I don't know much about cars other than how to put coolant in and how to check my oil. I need an idea of what I'm looking at so that I can budget for a repair.

If anyone can help me know what's going on, thanks!!!

03-23-2011, 08:03 PM
The blower fan is sealed, no repairs can be made, have the alt. output checked, if ok more than likely the blower relay resistor pak is bad, again someone has to check this when it occurs.

03-24-2011, 07:58 AM
Is the fan speed slowing or is the temperature from the vents not remaining constant?


03-24-2011, 09:11 AM
Is the fan speed slowing or is the temperature from the vents not remaining constant?


The fan is slowing. The temperature is always correct according to the setting once the engine warms up.

03-24-2011, 10:02 AM
what fan are you talking about??the fan for the heat/ac in car
or the fan for the radiator under hood

03-24-2011, 01:55 PM
If the blower motor is physically slowing, that's either due to a wiring issue (including the blower motor resistor), a charging system issue, or a problem with the blower motor. I suppose there's a slight chance there could be a restriction in the inlet air path that causes drag on the blower motor when the vehicle is not moving, but that would be one of the last areas to check, or you could easily switch between "Fresh/Norm" and "Recirculate/Max A/C" to change the inlet path to see if it has an effect.


03-24-2011, 08:37 PM
Thanks for the suggestions. I'll have it checked out, hopefully this weekend.

~ Aubrey

03-25-2011, 08:15 AM
Check the electrical plugs on the resistor and the fan. It sounds like one I had here and that fixed it. The plug on the fan was melted and the plug on the resistor was starting to do the same. The plug pigtails were available at napa.

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