I just love the wisdom in here-- thanks Bill. and everyone else.

 

Are you SURE that you had the gages connected properly? Ive NEVER seen this issue before


I'll check the connections again this evening, but I thought I had them connected properly. At one point, after hooking up the hoses, I opened the left hose to the air out and noticed some refrigerant gas as well.

Thanks again for your help.

 

Bill and others who may be following my a/c problem:

I hooked up the gauges this evening. The car had not been started since yesterday. Both the low and high side gauges read about the same, around 100 and 110. I started the car and the numbers did not change initially, however, the pressure on the low side gauge started to climb as the engine warmed up. The compressor was running as it normally does.

Just in case the gauges were wrong, I connected them to one of the other cars and the gauges appear to be fine.

Does this give anyone clues as to my problem? Could the orifice be the problem? Are other components suspect too?

I appreciate any help you guys can offer.

Thanks

Dan

 

My ac is not cooling. I hooked up the guages and it read 80 on the low side and 100 on the high side. I started the car and ran for 10min with the ac on full blast at its coldest setting, checked the reading at idle, it read 70 on the low side and 140 on the high side. I increase the rpms to 2000 for 5min and the low side read 75 and the side read 140. The air temp was 65. Can anyone out there tell me what all this means???

 

Plasticfan & Bill, thanks for some great info. This is why I love this forum.

 

Are you sure that the compressor clutch is engaged and the compressor is actually turning? When you turn the AC to ON, does the light in the button blink?

Look at the center of the compressor pulley when the compressor is suppose to be running. Make sure that the pulley and the center hub are both turning.

BC

 

Yes the compressor is running when on the center part of the pulley is turning, when off the center part is not turning. The ac button blinks when I turn the ac on.

 

If your car is reading 60-80 on the low and only 100-120 on the high, then either your compressor is bad or you are really low on freon. If it happened suddenly, then most likey your compressor blew up.

 

The compressor seems to be running, at least its spinning from the a/c belt. How can you tell if the compressor is bad, even though it is spinning?

 

THE READINGS your seeing! The compressor is NOT building pressure. You can try to add r-134 and see what happens.

(one can at a time and see if you can acheive the PROPER pressures )

BC

 

okay, I will give it a try. Have get some R134a, do I need oil.

 

My ac is blowing cold air on the passenger side and warm air on the drivers side. The system is fully charged, compressor is working fine along with the cooling fans. It has the duel zone controller which is also functioning as it should. Could this be a bad actuator motor on the vent on the driver's side? thanks!

 

How do you know it working correctly?? Pull up the DTCs in the DIC and see if there are any HVAC DTCs.

READING YOUR Engine Diagnostic Codes (DTCs)

The Diagnostic Display Mode is entered with the following procedure:
1) Turn on the ignition but don't start the engine.
2) Press the RESET button to turn off any warning messages. (i.e. door open, trunk open etc…)
3) Press and hold OPTIONS
4) While holding OPTIONS, press FUEL four times within a 10-second period.

Initially, on-board diagnostics go into an Automatic Mode which shows diagnostic codes in a pre-set sequence: PCM - TCS - RTD - BCM - IPC - RADIO - HVAC - LDCM - RDCM - SCM - RFA. All codes will be displayed for each. ( i.e. PCM = 4 codes)
If none are present in a given module, you will see No More Codes on the display.
There are two kinds of diagnostic codes, Current and History designated with a letter suffix, C or ;H. A current code indicates a malfunction is present in the module displaying data. A history code indicates a problem existed sometime in the last 40 or 50 ignition cycles. When not accompanied by a current code of the same number, it's potential evidence of a previous problem, now resolved, that was not removed by clearing the codes.
More likely it's an indication of an intermittent malfunction.
Intermittent codes are the most challenging of the diagnostics. An intermittent code may have happened once, may have happened more than once but is inconsistent or may be happening on a regular basis but not at the time the codes are displayed. History codes can also be caused by a current malfunction in a system that is not operating at the time codes are displayed. An example is the rear window defogger which doesn't operate until the Body Control Module detects engine rpm. For history codes set by a module that does not operate with the key on and engine off, a special diagnostic tool called a Scan Tester is necessary to properly diagnose the malfunction.
Once the system has displayed all modules, it goes into the manual mode which allows selection of each module using combinations of Driver Information Center buttons. Manual mode can also be entered during the automatic sequence by pressing any button except E/M. Once the display shows Manual Diagnostics, select a module by pressing the OPTIONS button to go forward or the TRIP button to go back. Once a module is selected, a code is displayed, and if more than one are present;
press GAGES to go forward or FUEL to go back.
To exit the diagnostic mode at any time, press E/M. If you want to erase codes in a given module, press RESET
To reset the codes once in manual mode, press and hold RESET until it displays NO CODES Press OPTIONS to go to the next module. Repeat the steps until you have reset the codes in all the computer modules.
NOTE!! Only reset the codes IF you want to - it is NOT necessary to do this. Clearing a code does not repair a problem. You are simply erasing the evidence of it in the module's memory. If you clear the code/s, and extinguish the Check Engine Light, your emissions status ready will NOT allow you to pass an emissions test until you have completed the required driving cycles.
Once you have the codes, the next question is: What to do with the information?
First, consult the factory service manual. Any serious C5 Do-It-Yourself owner should invest in the Corvette Service Manual of the appropriate model year. The Service Manual is really a requirement if you want to understand and work on your C5.

Here is very good site of DTC definitions:


http://www.gearchatter.com


Make sure to include the H or C suffix!!

 

I put in a can 12oz, if R134a the temperature in my vent was 77-78degrees. The low side was 75 and the high side was 104 with ac off. I connected the freon and put in the whole can 12oz with the engine running and the ac on high, took about 20min. The air Vent temperature was 75-76 degrees, the low side stayed pretty much the same at 72, the high side went up to 200. The outside temperature was 87 degrees. Should I put in another can of freon?

 

I put another 12oz. freon. To start the low side was at 110psig, the high side was at 100psig. The outside temp was 84 and the temp on the vent was 94. I started the car and put the ac as cold as it would go and the fan on high. At idel the readings were as follows, low side 75, high side 103, vent temp76. I began putting in the freon and after it was all in the low side read 70-71 and the high side 200, the vent temp went down to 73-74 degrees. The compressor was quite and running all the time, did not cutoff. Could I have a clog somewhere in the system? Any help would be appreciated.

 

If you had a clogged system, you would see a really low low side and a high high side.

Most likely your compressor is toast and not building enough pressure, another angle is its like your orafice valve is missing and its just blowing through....I have neve seen this.

Probably compressor is toast.

 

Thanks for the information regarding the compressor. I have a question if the compressor was bad, wouldn't it quit cooling altogether. I certainly do not know that much about a/c's, but I was just wondering why it got a little cooler after I put in another can of freon. Does anyone know how much freon the system takes, and could another can possible improve the situation, just a thought. Any help or recommendation are certainly welcome.

 

The compressor is an electro-magnetic device. The clutch engages and spins the internals creating pressure. Your's is not creating preassure (i.e. a bad seal, valve, etc ...) Kind of like a blown head gasket, you can see it until it's apart.

 

Theres a pressure regulating valve inside the compressor. Thats most likely bad. You just need to replace the compressor, the receiver dryer, the orifice tube and all the necessary oil for the new parts.

Make sure that you use ALL new O rings and the correct amount of R-134. You also need to vacuum out the system and make sure that it holds a vacuum.

You really need to obtain a service manual and follow all the guidelines for AC service. Short cuts will cost you LOTS of money in the future.

BC

 

Thanks everyone, I think its time to take it to the A/C repairman.