hi all, compressor cycling every 2-3 seconds and no cold air or cold lines near accumalator.
lines where replaced about 3 years ago and orphace tube. by GM. low pressure switch replaced last fall. no rough sounding compressor. air was fine last fall when using system. the only thing i gathered is low pressure switch will turn compressor off right away if low pressure hence the on/off cycling every 2-3 seconds i dont have pressure gauge. thanks in advance for any advice i live in a state where you cant add your own refridgerant
it is a 95 blazer

 

Sounds to me like it needs a charge, when the compressor is off there is enough pressure in the system to turn it on but as it turns on the pressure drops and turns it off

 

Definitely the most common cause.

 

X2 err 3 but check for a leak or have a shop check for it. There has to be a leak somewhere at a fitting or hose etc for it to drain down over a winter.

 

Go to discount dollar or drug store toy section..
get some..


Use a 1/2 paint brush and coat all joints with it. Best to coat with suds but just the liquid will usually do.

I have a 400 dollar sniffer but this is how I isolate the leak once I find the general area

If you're too chintzy to spend a couple bucks on that.. next best is about 1/3 cheap baby shampoo 2/3 water.

 

Yup & if it's down on charge you can get a can of the refrigerant ($20 or so) & charge it. Then it'll have the pressure for you to find the leak.
Still a small price to pay to find the problem instead of replacing things that don't need replacing.

 

Rotti, it has the pressure already to find the leak.

There has to be 30 psi over atmosphere for the accum switch to close and allow compressor clutch to engage.
If there were no liquid then the compressor would stop in a second or less. so obviously there is liquid still in there.
If there is ANY liquid refrigerant at all in the system then the at-rest system pressure equates to the ambient temp.
Thus adding more refrigerant would not make any difference in the pressure.
No matter how much liquid refrigerant is in system, as long as there's even a teaspoon, here's the pressures at ambient:
32F = 37 psi, 50 F = 54 psi, 70F = 69 psi
So.. how to tell for sure.if there's any liquid: Let compressor cycle. trace the line from the condenser to the firewall. There will be a pinchpoint or fitting for the orifice tube. At the point where the orifice lies, there should be cold when the compressor runs. That means there is liquid on the other side {toward condenser}
I use that method to find natural gas leaks at far less pressure than thirty pounds. obviously the compressor doesnt have to run to find even tiny leaks.

 

thanks for all your help, system was recharged after finding no leaks, and rechecked 2 weeks later using a black light as well, still no leaks and working great. should hit the 200,000 mile mark in next month or so. still going strong. thanks again!