Hi all,
I have a problem with my 1995 Q45 which I am hoping to find some answers for. Sorry if I don't use the correct lingo, I love my car, but don't know all the intricacies of everything under the hood.
Here goes:
A few weeks ago while cruising at highway speeds, the A/C all of a sudden started to blow hot air. It wasn't gradual or anything, in 1 second, it went from cold to hot.
Took it to my regular mechanic, he said he replaced some hoses etc and recharged the A/C. It works somewhat OK now but never as good as it was. It blows cool instead of cold and only when set to 65 degrees at full blast.
It takes maybe 10-15 minutes of driving to get the car somewhat cold, and I just hate it.
Took to the mechanic again. He checked to see if there were any leaks and told me that all the freon he put the last time (2-3 weeks ago) was still in there (no leakage). This time he showed me a fan in front of the car that wasn't spinning (when the engine is on) and gave a price of $380 (including labor) to get it replaced. ...
I don't know what this fan is for, as I see a big white fan maybe a feet or so behind this fan that is working fine.
Does this fan all the way in front the engine has anything to do with the A/C? Maybe a compressor cooler or something?
I don't know.
Any suggestions are dearly appreciated and most welcome.
Thanks in advance...
Danny
FYI: I live in Miami, Florida where the temprature is always more than 90F.
Q45 A/C Problems
The fan is definitely related to the AC--it's the condenser fan for the AC. The condenser is the "other radiator" just behind the fan, in front of the engine radiator. The condenser cools the hot refrigerant after it's forced through the compressor. The fan may or may not work; the only way to be certain is to apply 12v straight to its terminals. If the fan works then something else is at fault, maybe the temp switch or the pressure switch--the things that control the fan's on/off relay. It should turn on when the AC is turned on.One cheap technique is to start the car when cold, turn on the AC, and then spray a fine mist of water onto the condenser. If the AC goes cold then a working fan may help enough.Did your AC guy measure the hi and lo-side pressures of the system? I don't get much confidence from your post that your tech did enough proper diagnosis of the system to determine what's wrong. Throw on a few hoses and top off the system--not a good approach.If you have a factory manual there's a procedure in there for doing a self-diagnosis of the system. It may or may not pick something up. If it does then you have a place to start. If it doesn't, then you'll have to find a competent tech that knows how AC systems work and how to troubleshoot them properly.
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Q45tech
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- Car: 1990 Q45 342,400 miles 22 years ownership with original engine
1995 G20t 5 speed 334,000 miles 16" 2002 wheels - 205/50/16 Sr20ve vvl
10 year old AC system need rebuilding to achieve as new performance...............hopefully with proper previous maintenance you don't have to replace all $2700 in parts.........at least at one time.
Failure to change receiver dryer at reasonable intervals [every 60k] is the step that starts the failures. Same with not checking/ replacing Compressor oil.
The thing all 94-96 Q [have done 2 1993 Q also] owners much watch out for is a sticking heater mix door. Failure to exercise the door weekly, monthly will allow it to stick and break the plastic hinge...........this is an unbudgeted $1000 you don't need to waste.
When AC is marginal, the system never calls for some heat to maintain the inside temperature on highway. So owners may go for 3-4-5-6 months [Summer] with the heater mix door never moving. Whereas an as new AC will call for 10% heat to maintain a 47-50F center outlet temp........otherwise after 15-20 minutes the outlet will be 44F with no heat added in recirculate position.
Failure to change receiver dryer at reasonable intervals [every 60k] is the step that starts the failures. Same with not checking/ replacing Compressor oil.
The thing all 94-96 Q [have done 2 1993 Q also] owners much watch out for is a sticking heater mix door. Failure to exercise the door weekly, monthly will allow it to stick and break the plastic hinge...........this is an unbudgeted $1000 you don't need to waste.
When AC is marginal, the system never calls for some heat to maintain the inside temperature on highway. So owners may go for 3-4-5-6 months [Summer] with the heater mix door never moving. Whereas an as new AC will call for 10% heat to maintain a 47-50F center outlet temp........otherwise after 15-20 minutes the outlet will be 44F with no heat added in recirculate position.
Fixed
Thanks for the advice guys.
Just for the hell of it, I took it to another mechanic. Apparentky the first one didn't put enough freon in the system and according to the new mechanic the condenser fan wasn't kicking in because of low pressure in the A/C system.
He recharged the whole thing and the fan kicks in now, and there is a considerable difference in the cold output.
Thanks again guys for all the advice.
Regards,
Danny
Just for the hell of it, I took it to another mechanic. Apparentky the first one didn't put enough freon in the system and according to the new mechanic the condenser fan wasn't kicking in because of low pressure in the A/C system.
He recharged the whole thing and the fan kicks in now, and there is a considerable difference in the cold output.
Thanks again guys for all the advice.
Regards,
Danny