Strange Air Conditioning Problem

I live in Phoenix - temps are up around 110-115... Yesterday my 97 Blazer LE Air Conditioning was running - but not cooling anywhere near what it normally does. I checked the pressure and found it was about 65 lbs - so bled it down to about 35 lbs - the system started cooling better - but the compressor started cycling 5 sec on - 5 off... Then noticed air was getting warmer. Added freon to 45-50 lbs and it got even hotter... (compressor still cycling 5 on - 5 off)

Bled the system all the way down - put in a can of oil and a can of freon and was reading about 45-50 lbs - compressor is still cycling (5-5) and the air is blowing just barely cool... (maybe 85-90 degrees)

Also yesterday noticed while sitting idling in traffic - water temp was up around 220 (normal 190) - no water in reservoir - so I put in about 3/4 of a gallon of coolant into the reservoir...

Idling today - it got up to about 250 (just short of red line) - the engine is running extremely smooth - got home and checked the reservoir - the level is the same - but was steaming hot... (which makes me tend to think that it is circulating...)

So my 2 problems are: A/C is just barely putting out cool air (at 45-50 lbs) and my cooling system is starting to overheat - Could the A/C be related to the Cooling problem (don't think so - but ???) I bought the truck 8 months ago - and they replaced the water pump when I bought it - so I'm assuming the pump is (hopefully) okay - does this sound like a stuck thermostat?

Any advice would be greatly appreciated (it be gettin nasty hot out here...)

Thanx,

Dennis

Thermosat sticking? Low pressure switch on AC?

Thermosat sticking? Low pressure switch on AC?

Thanx for the reply - I'm really totally stumped on this - here is what I've done so far:

I took it to a shop that did a $25 diagnosis - here's what they said:

Leakage at AC Compressor Seams - Will Need Compressor - Accumulator - Orifice Tube - Flush And Charge - and they wanted $950

Not having that kind of money - a friend and I decided to do the job ourselves...

Over the past 2 days - here's what we've done...

Replaced the Thermostat
Replaced the Compressor and Clutch (with remanufactured)
Replaced the High Pressure cutoff (on the back of the compressor)
Replaced the Accumulator
Replaced the Sensor on the Accumulator
Replaced the Orifice Tube
Pulled 28 pound vacuum for 30 minutes (held pressure)
Put in 1 can of Oil
Put in One Can of Freon

The pressure built up to 50 lbs - the system got just a hair above cool - but not at all "cold"...

When we put in the second can of Freon - the compressor started cycling every 5-10 seconds - and the system started blowing warmer air...

The compressor is kicking out at 185 lbs (high pressure side) then when the pressure drops - it kicks back in - then continues cycling...

The low side pressure is now reading 70 lbs (Is it safe to put in a third can of freon??? - this is Phoenix and it's hot outside...)

Having read that pulling the connector off of the sensor on the accumulator and jumpering across it - the compressor will (supposedly) keep running - we did this - but it didn't have any effect - the compressor continued to kick in and out anyway...

We've replaced everything that we can think of and it hasn't changed anything...

I'm beginning to wonder if the rebuilt compressor is defective???

No idea of what to try next...

Any help would be GREATLY appreciated!

Dennis

Are you testing the pressure with the AC on MAC and the fan on full blast.

Are you testing the pressure with the AC on MAC and the fan on full blast.

Thanx LT - we finally got the AC running last night - I called Autozone (where we got the rebuilt Compressor) and talked with the guy - told him everything had been replaced that could be replaced and I was thinking the rebuilt compressor was bad... He told me to bring it in and they'd exchange it - when I got there he went over a number of things with me - one of which was the fan clutch - I remembered that the fan was VERY easy to turn (both directions) and he suggested replacing it (that even if it wasn't the problem now - it would cause problems for me later...) So, I took the "new" compressor and the fan clutch - installed both and the difference was like night and day!!! - I'm not sure which was the problem - but it's working and that's whats important...

I bought the Blazer in November and it started giving me problems within 4 months - First it was electrical - the entire system would die while driving - then come back on before coasting to a stop - I took it to the Chevy Dealership - they kept it overnight then told me the fuel pump was the problem - they wanted $1600 to drop the tank - put in a fuel pump and clean the injectors - I couldn't afford that so took it home and asked a friend to take a look at it (it was still running)

We took it on the freeway and it cut out totally - came to a stop and wouldn't do anything - he had me pop the hood - grabbed the battery terminal and twisted it and power came back on - I started it - we drove back home - tightened the terminal and it ran fine for 3-4 months.

Then about a month ago I got on the freeway and it wouldn't go into high gear - not only that - it wouldn't go into low gear either - took it to AAMCO - they kept it overnight then called and wanted to rebuild the transmission and put in a new torque converter - They wanted $2000 for the job - (which I couldn't afford) so I brought it back home and started checking the forum - saw where the ignition switch problem might be what was causing it - so $88 later - it's working fine... (until last week when the AC went bad)

I figure that if I'd done what the shops wanted - it would have cost me more than $3,000 - and NOTHING would have been fixed!!!

You can imagine how happy I am about having the forum available!!!

THANK YOU!!!!

Dennis

You are welcome.

Dang arizona shops sound like they are charging way to much for any work they do.Its great that you gave it a shot and fixed all the problems yourself kudos on that.