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AC cooling concern and questions not over heating car
AC cooling concern
1990 GTA 305 five speed
Today 110 out. Lower humidity. Running on freeway about 5 miles.
Car normally runs about 195 to 200 with a 195 stat. With the AC on maybe to 220 on the gauge. This is with the temp about 95.
Back to today. The fans are on. Driver side is always on when running. The pass side fan is wired to a relay and a switch. When I turn on the AC I turn on the switch.
The temp on the gauge showed 190 and then slowly went to about about 245. So not overheating just a little too warm.
When this happened the cool are got not so cool. Which I think makes since because the condenser was letting off heat as it should.
Turn off AC and the temp went back down to about 200. This aways where it runs with out the AC on.
Opened the windows to get some relief.
New OSC Cooling Products 951
New stat
Air dam in place and leaned forward to maximize air scooping.
new rad cap
proper coolant amount Burped
Condenser fins were straitened and was cleaned front and back
New hoses
Etc.
The fans are original or maybe stock replacements.
How much air are they supposed to move? Possible maybe the motors need replacing?
I want to add a fan controller to automate the fans and not use the block coolant switches. Any recommend types or company?
AC system is using fr12 and was done by a AC shop.
When the AC was brought back to life it was a cool day and the system worked great as it has on not so hot days. Could the freon pressures be off? Of course I know nothing about AC and can guess with best of them.
So I am not sure where to go next or really what ask.
It would be nice to drive the car when it is hot out. And not be sweating.
Yes, however before you attempt a fix, is the repair still under warrantee?
If yes, bring it back.
If no, you can use a pressure gage to find out if the pressure is correct.
On an 85° day, 50% humidity, with the A/C running, with R12, the low side should be about 58PSI.
The high side should be about 240PSI.
Also you should know in most cases you just have to measure to low side when you’re doing a quick check to find out if you lost Freon.
On an 85° day, 50% humidity, you should have air coming out of the vents no higher than the mid 50’s.
Stop & Go traffic might cause higher temps due to less airflow the condenser.
Make sure your blend-doors are operating full swing and not getting stuck causing too much outside air to come in during the recirculate mode.
Re: AC cooling concern and questions not over heating car
It's hard to put any kind of number to "how much air" for a stock fan.
But if yours are old, they yes definitely, they could be running much slower than they used to, and not moving as much air.
You might want to look into newer fans off of other cars. The Taurus/Sable/etc. unit from the mid 90s is a favorite. Xler minivan ones also. Both of those are said to be a pretty good fit, in addition to moving ALOT of air. There may be plenty of others but I can't give you specifics. A walk around the junkyard with a tape measure might be informative. Ones from GM cars might require less changes to the wiring.
You can buy any of that sort of thing new, for maybe $100 - 125 or so, from places like RockAuto, 1AAuto, etc. Get any supporting pieces at the boneyard then get new fans. Use relays, DO NOT try to use switches to control the motors directly; and use BIG wire for them, #10 preferably, to avoid voltage drop in the wire.
As far as controllers, if it was my car I'd do away with the switch and put it back to stock configuration, with maybe a lower temp fan switch than stock.
Re: AC cooling concern and questions not over heating car
Good Friday Sofa
So this morning I went ahead and put the wiring back to stock for the aux fan.(the one on the pass side). So I assumed that when I turned the AC on the fan should have started up. No joy. So reading the manual (GM) page 8A 31-14. Part or the trouble shooting is to ground out the aux coolant fan switch. The question is how do you get to it? The only way I see is to get it up in the air or at least on ramps. Actually i'm hoping it is the relay much easier to get to.
Also ever since I have owned the car I have wondered what this senser is. To the left of the CTS. Nothing is hooked up to it and I cannot find any loose wires. Here is a photo.
I do say thanks to you and all the very experienced people here on third gen.
Thanks.
08-30-2017, 07:01 PM
