AC issues in Houston

[liquify33]

Hey guys, need a little help on troubleshooting. Here's what's going on:

Blower motor squealed in the winter, replaced it. 2 days later the passenger floor was wet, pulled the motor, cleaned all the leaves and pine needles I could from the evaporator area, no wet floor since, big AC puddle outside behind passenger front tire now. While this was going on, every 3-4 days I'd see a small puddle of oil-y fluid under the truck, just driver side of center. It didn't smell like PS fluid, and wasn't coolant, kinda light pnk. After a good drive with AC going, I hear a draining/winding down noise at shutoff coming from the general blower motor area, is that normal? 5-10 secs usually.

Once it started getting 95+ hot the AC felt warm and I did what any idiot does and bought one of those cans at autozone with the gauge and the bullcrap promises. That didn't help and I ended up overfilling the low side because I only had front AC running. I released the excess, got the psi in the right general area and it's held steady, only the air is still warm up front, much cooler in the back vents.
I'm going to my dad's this weekend for gauges and a vacuum pump.

My plan is to hook up gauges with truck off, check for equilibrium, then check gauges with both ACs running max.
Questions:
Is there a way to check compressor oil level while it's on the vehicle?
Can I just add some PAG150 on the low side *if* I vacuum and recharge? How much?
The compressor gets HOT, I'd like to run it properly.
Why would rear AC be colder than front using the same system?
I only have a fan speed control for rear AC, no temp.

 

[Timbers]

I can try to help you but I'm not an expert. Your front AC is not as cold as the rear because your evaporator coil is probably covered in crap. You can find this out by removing your blower motor under your dash. Look up inside there and see if there are leaves and other debris caked onto the evaporator. If there are you can carefully remove them and vaccum it out. I would not blow it with compressed air as I just did this with mine and I think I made it worse. Your rear is cooler because its not used as much and still has good air flow.

Your oil question is a tough one. Usually when a system leaks refrigerant its a slow leak and the oil stays in the system. You can recharge with straight R134a and still have the same factory amount of oil in the system. There is no way to check the oil level in your AC system. The only way would be to flush the entire system and recharge with the factory amount of oil and the factory amount of refrigerant.

Not sure if you are thinking the puddle under your car is all your PAG oil or not. I would imagine if it is then your compressor would be covered in oil especially around the pully/clutch area or back where the fittings connect to it.

In my experience when the system is low the compressor will either not run at all or run for under 8 seconds and shut off, then another 8 seconds and shut off. You can try filling the system, with your AC on MAX and the engine running, try filling until the compressor stays running. Then you know the low pressure switch is happy with the pressure it is seeing.

Of course the best way to fill it would be to discharge completely, then read the amount of refrigerant that the car requires "usually on a sticker on top of the accumulator on the passenger side", and fill it with the exact amount.

Make sure you run your rear AC when doing this too.