[crashyyz]

compressor cycles.. the lines and condencer are ice cold and sweating .. just inside when i change temp with the ATC (auto temp control) .. or hit the AC button, the temp doesn't change. the compressor kicks on.. everything goes great on the ouside... not on the inside. blows just as hot as with full heat on.

anyone havea diagram of where the blend door is on this 1990 new yoker?

thanks again

 

[crashyyz]

first off thanks for the speedy replies..

One A/C line should be cold and one hot. If both are cold you have a problem. What is the service history of this system? Has it just been recharged? Who did it? Was it properly evacuated first?

one is cold one is hot. it ran fine until this summer. it was just topped up with red tek (that synthetic crap). my mother didn't know any better and the place changing her oil did it. that being said, I think it was also topped up with the same stuff 3 years ago when we got the car and ran fine until this summer. the sealant was not used, only the refridgerant.

The compressor should be the 6C17 on this car... it's a variable displacement unit that should not cycle. Anytime the outside temperature is warmer than a few degrees above freezing, the compressor should be always be engaged with the ATC on. The fact that it cycles suggests a problem. This system is hard to service unless one knows exactly what one's doing. That compressor doesn't like anything but R12. It can be made to work with other refrigerants, but it'll make you jump through some hoops first.

As for the blend door, I'd run the ATC self test and see if it throws a code first. Press and hold auto, floor, and defrost until the display starts flashing. It'll run the test and show codes in the display. If it does, press the panel button to continue testing (this part has never worked for me though). Otherwise, the blend door servo is under the airbox by the accellerator pedal.

While you're at it, maybe check that your aspirator fan is working... it's located behind the instrument cluster. These love to fail. Any 1988-1993 ATC equipped car at the salvage yard can give you a replacement. The Imperial has one from a 1988 New Yorker in it. You should be able to hear it working faintly if you turn the ignition to the run position without starting the engine and turn off the ATC.

I will double check when the compressor is running and if constant or cycling. I got home so late with the car last night and only turned the ac on for about 10min to see if it would cool. I was tired and maybe should have paid better attention. will auto try running the self test and check the aspirator.

Condenser in front of the radiator should be warm and the radiator fan motor running.
The evaporator under the dash should be cold.
Do you hear the doors change when selecting temperature/modes?

I don't hear the doors changing when selecting temp. will check the evaporator. condensor is warm and the rad fan was running.

will post my findings... thanks again everyone

 

[crashyyz]

WOW! .. I'm excited. I have AC again and it's ICE cold. turned it on .. fans running, compressor constant (the cycling was obviously my mistake). so I ran the self test and I heard the blend door .. bam! cold air. no codes. so it had gone into some weird mode and just needed reset I guess. thanks again soooo much for your help. might have to keep this ol baby afterall after getting my mother a new ride. just need to fix the odo problem and it's good to go.