A/C problems...

[tybrenis]

Hey guys,

My A/C just isn't blowing cold this year for some reason. My first thought was that with the FMIC sandwiching the condensor between it and the radiator, that the condensor just couldnt get cool enough. So I added a spal fan to the radiator again to turn on with the AC, since before the car was running a single radiator fan.

This seemed to kinda help, but didn't do much. The engine temperature was way cool, however. So, I bought a charging kit to charge the car's refrigerent. However, before I ever charged the system, I checked it with a gauge and found the pressure to be at 75 psi on the low side with the compressor running....way too high. So I took the car to a shop and had them drain it and refill it to the correct pressure.

Still no improvement. The mechanic tells me he thinks the radiator and condensor just can't get cool enough, and I need better fans. So I added two news fans to the front of the radiator, a 10" and a 12", as compared to the stock 12" and a somewhat lame 8" spal fan. They provide wicked air flow, but the AC STILL only gets cold when the car is first on, then as soon as the engine warms up it is quite weak.

Perhaps it's the 90+ degree weather we've been having lately. I move to the Miami area in two weeks, so I want the AC to work. Does anybody have any other ideas?

 

[GTRay7]

get it up to temp and spray the condenser with a hose. if the temp drops at the vents then you likely have an efficiency problem with the system. This may also be a deeper problem. Get the full report on the compressor pressures for the low side AND the high side. this can help you diagnose a failing compressor or a restriction in the system preventing the expansion device and evaporator core from doing their jobs. also, dont forget to check your cabin air filter!

Ray

 

[NCoppersmith]

It may be that the AC just can't handle the temps. I was in MS the past year and my P5 can't blow cold air when the engine is warm at idle. Get the car moving over 35mph and it's fine. I have a corksport radiator and dual 12inch SPAL fans. My IAT was showing 160 degree temperatures and at idle my coolant temp could go as high as 240. This was with the outside temp running in the 90's every stinking day for the month of May and June with ungodly humidity (which Miami will be just as bad methinks).

 

[ucMP3]

It may be that the AC just can't handle the temps. I was in MS the past year and my P5 can't blow cold air when the engine is warm at idle. Get the car moving over 35mph and it's fine. I have a corksport radiator and dual 12inch SPAL fans. My IAT was showing 160 degree temperatures and at idle my coolant temp could go as high as 240. This was with the outside temp running in the 90's every stinking day for the month of May and June with ungodly humidity (which Miami will be just as bad methinks).

240 is pretty ******* hot... Your coolant really shouldn't get that high. You may want to look into that...

 

[GTRay7]

Like i said, spray it down with a garden hose - the cold water out of the hose will transfer orders of magnitude more energy away from from the condenser/radiator assembly and the temps should plummet in the cabin.

You can also install a pusher fan in front of everything to see if that changes anything.

Ray

 

[tybrenis]

Like i said, spray it down with a garden hose - the cold water out of the hose will transfer orders of magnitude more energy away from from the condenser/radiator assembly and the temps should plummet in the cabin.

You can also install a pusher fan in front of everything to see if that changes anything.

Ray

I think you've got it right with this solution. I even have the fan to install. However, I'm really unsure as to how I would wire a third fan.

 

[GTRay7]

I think you've got it right with this solution. I even have the fan to install. However, I'm really unsure as to how I would wire a third fan.

simple... wire it for power from a 30amp relay with a switched lead off of the ignition - always on.

Ray

 

[thecrash91]

if your coolant is that hot how hot is the engine? you sure you have enough coolant in the tank? have your mechanic check high and low side, could be a damaged pipe or something causing a clog.

 

[tybrenis]

if your coolant is that hot how hot is the engine? you sure you have enough coolant in the tank? have your mechanic check high and low side, could be a damaged pipe or something causing a clog.

Checked high and low side. Both were too high, drained and recharged the system and now both are fine. The engine runs perfectly fine, there is enough coolant in the tank.

The car blows pretty cold air but only at the "2" fan speed. Any higher fan speeds, or if you are idling, forget about it.

Ray - You'll have to explain the wiring a bit further. I can wire but I can't picture that in my head - I'm no schematics guru

 

[hoindawall]

I agree with ucMP3. 240 is pretty hot. It's possible your thermostat may be stuck partially closed causing higher than normal engine temps, which also cause higher a/c condenser temps that equal warmer air out of the vents. I'd try replacing the thermostat and flushing the cooling system. When was your cooling system last serviced?