smelly ac??? 99 grand prix
9baller
10-11-2014, 08:59 PM
hey ya, my 99 grand prix smells when ac is turned on. but yesterday I noticed that the smell was there with no ac on.
question is dose the 99 gprix have a evaporator coil and how do I get to it. also how about a filter for ac.
the drain works, what type of cleaner is recommended.
this car has only 75000 miles.
question is dose the 99 gprix have a evaporator coil and how do I get to it. also how about a filter for ac.
the drain works, what type of cleaner is recommended.
this car has only 75000 miles.
Tech II
10-12-2014, 07:30 AM
If you have an air filter, it is located underneath the plastic cowl, which is located underneath the passenger wiper blade....remove the wiper arm, remove the retainers of the cowl, and lift up, and you can slide out the filter...
What causes the smell with the AC on , is usually bacterial growth on the fins of the evaporator.......with humid conditions, when the AC is turned off, that water that is condensed on the fins is a breeding ground for bacteria.....
One way around this, is to install an after blow module, program it on, or manually do it......
The after blow module was installed in GM cars in the 90's.....it would monitor how long the AC was running, and based on that, when the vehicle would be shut off, the module would turn the blower motor on for a certain amount of time to dry out the fins of the evaporator.....you have probably walked by cars in the summer, that weren't running, but heard the blower motor running...
Newer cars, had the ability to program the HVAC module, to do the same thing.....if you had this problem, you would bring it to a GM garage, and they could "program" it to work the same way ......
But you can also do it manually........If it is a real hot, humid day, when you are done driving, park the car, shut the AC off, leave all the windows closed, in recirculate mode, turn the temp selector to full hot and blower on high, for about a couple of minutes......you will be recirculating hot air across the fins, which will quickly remove moisture from them...
Now if the horse is out of the barn, and you have a mold smell already, you can remove the cabin filter, turn the blower motor on, and spray something like Lysol down into the fresh air intake, and the blower motor will circulate the Lysol through the evaporator fins, attacking the bacteria....
What causes the smell with the AC on , is usually bacterial growth on the fins of the evaporator.......with humid conditions, when the AC is turned off, that water that is condensed on the fins is a breeding ground for bacteria.....
One way around this, is to install an after blow module, program it on, or manually do it......
The after blow module was installed in GM cars in the 90's.....it would monitor how long the AC was running, and based on that, when the vehicle would be shut off, the module would turn the blower motor on for a certain amount of time to dry out the fins of the evaporator.....you have probably walked by cars in the summer, that weren't running, but heard the blower motor running...
Newer cars, had the ability to program the HVAC module, to do the same thing.....if you had this problem, you would bring it to a GM garage, and they could "program" it to work the same way ......
But you can also do it manually........If it is a real hot, humid day, when you are done driving, park the car, shut the AC off, leave all the windows closed, in recirculate mode, turn the temp selector to full hot and blower on high, for about a couple of minutes......you will be recirculating hot air across the fins, which will quickly remove moisture from them...
Now if the horse is out of the barn, and you have a mold smell already, you can remove the cabin filter, turn the blower motor on, and spray something like Lysol down into the fresh air intake, and the blower motor will circulate the Lysol through the evaporator fins, attacking the bacteria....
9baller
10-12-2014, 12:27 PM
Thanks a lot. Your post should be very helpful.
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