1999 Mazda 626LX 2.0L I4 small engine: the driver side radiator fan only has one speed and does not go to high speed when the airconditoner is activated … like the passenger side fan does. We think this is why we sweat at stop signs, red lights. Would a replacement fan fix this problem and go to high upon AC activation? Local dealer - no response zip 77845 Texas 110F heat. HELP!
Probably not. The drivers side would be the radiator fan, responsible for keeping the engine “cool.” The passenger side fan would be the AC fan, responsible for kicking on to keep air flowing over the AC coils when you’re stopped. There’s no way that fan is going to move as much air over the coils as you get at driving speeds.
You probably sweat at stoplights because your AC system has a slow leak, and you don’t have enough refrigerant to do the job anymore. You should have the AC system inspected. Don’t let the dealership do it - they’ll charge a lot more than an independent shop.
Your suggestions will get respect & attention, with my appreciation. May I offer 2 more observations & see if you have the same or slightly different angle to pursue?
- The AC “radiator” is in front of the engine radiator and both are wide enough to be cooled by bother driver + passenger side fans located behind engine radiator. Therefore, IF there’s a a) high speed AC switch relay to a b) new fan capable of high speed … no one seems to know! This information seems key - any sources appreciated.
- My wife just dropped $777 at the dealer service dept. to make it trip worthy after 67,000 miles … they assured her everything AC was in good shape … until we were sweating bullets in Dallas 100F heat at idle - felt like a hair dryer. Once in city traffic, some relief but wasn’t until 15 minutes later on highway that we could turn the AC “down” a bit.
I am not aware of any sort of “high speed fan” setting. The fans are designed to run at the RPM that gives the best airflow efficiency. You are not going to get a 60mph wind out of a radiator fan no matter what you do.
100 degrees is pretty toasty, especially for a 12 year old car. Air conditioners are generally said to be working properly if they cool to 20 degrees below outside air temperature. That means the car would be 80 degrees inside. I personally would be sweating at that temperature too.
As for the money you spent to make it “trip worthy,” they probably looked at it, turned the AC on, felt cool air, and pronounced it good. I wouldn’t use that as proof that the AC system is properly charged.
The problem could be with the blend door, inside the HVAC system under the dashboard. The blend door controls cabin air temperature by “blending” cold air from the AC evaporator with hot air from the heater core.
If the door is not operating properly you could be getting warm air instead of cold air at idle, especially if the system in your 626 is vacuum operated.
I’d try an independent automotive AC shop instead of the dealer.
My wife reminded me that this/her car used to stop cooling at red lights … even when it was new - problem never waned since. The only car we’ve experienced since 1959 that does this.