A/C has correct psi but is not cold

My 98 grand am 2.4L is not producing cold air when on max.
I purchased a can of refrig. to charge system but gauge shows the pressure to be at 35psi. I checked the clutch on compressor to ensure it is engaging and it is. Air flow seems fine but just not cold. Is there a temperature sensor that could be bad?
thanks for any input.

Is the A/C blowing cold on the regular A/C setting?

Depending on where you live and how hot the temp's have been it may take a while for the car to blow cold on the max setting since the max setting recirculates the air from inside the car, if it is real hot outside and you are driving with the window down waiting for it to blow cold air it will take even longer, my wife was doing that and would complain that ut was not blowing cold. I had her put it on the regular setting until it cooled down a little then close the window and run it on max...she had to turn down the fan speed because it was getting too cold.

I hop this helps in your situation.

I almost forgot...Welcome to the forum. If my suggestion is not the problem let us know the people here on the forum are very knowledgable and we should be able to help resolve your problem.

Sorry fogot to mention my wife was the one who noticed the problem which I suspected the same thing you did but after my 40min commute home one evening I realized she was right (like always). None of the settings seem to cool the car.
thank you for your help

cars dont screw up cars women screw up cars.

cars dont screw up cars women screw up cars.

That really contributed to the thread. :eek7:

well I felt it related to the post before me.

It sounds like the evaporator core has an external blockage. Be prepared to spend some time on this one. You need to take the lower half of the dash apart on the passenger side to expose the core, make sure there is nothing caked on it. It looks alot like your heater core, which also bears a strong resemblance to a radiator. If that's not the problem, check all the duct work while you are disassembling everything, make sure everything works the way its supposed to. Expose the core, start the car and turn on the AC. The core should get really cold, if not the expansion valve might be stuck or the filter is clogged, they are both in the same place and usually require dealer or ac specialist service.

thank you, that gives me somewhere to start. Is the expansion valve located at the evap? I was told to check the low pressure sensor also, but if there was something wrong with the sensor would the compressor even engage?
thanks for the help.

If the low pressure sensor is not giving a reading, the compressor should not start. When its cooler out do you get cold air from the ac?

It seems cooler with outside air temp cooler, but its not cold air.

Did you also check the high pressure reading? And the 35 psi was at idle? You should check it at about 1500-2000 rpms and see what the pressure is or if the compressor is cycling off from the low-pressure switch.

the 35psi was at idle with fan on max. I have not checked the high pressure side. What is the normal range for the high pressure side of system?
thanks for everybodys input!
this is definetly a learning process for me.

Always check pressure with engine around 1500-2000 rpms (which is the normal operating level). This will give you a more realistic-operating reading. If its 35 at idle, using 134a, Id guess its just a lil bit low, probably not much. Try that and see if the compressor is cutting off as the pressure drops. Theres also probably a sight-glass indicator on the high-pressure side that you can check.

Just checked psi at higher rpm. It was still around 35psi at 2000rpm. I have started taking apart dash at evaporator location. cycled through defrost, ac and max settings to make sure all valves/vents are opening which they were.
I will keep everybody up to date with my discovery
thanks

I hope you are either really small or know someone who is.. I just had to dive into the dash on my 95 yesterday, ended up taking the passenger seat out to make it easier, still couldn't get in there very well.. Ended up calling the Hobbit (friend who is 5 feet tall) and he even had trouble. Good luck under there.