A/C Problems (97 Cobra)

[PJM99]

On my 97, I noticed this problem a few years back, only happened once in a while since, now it happens all the time.

The A/C will be working fine no problems, ice cold and then all of a sudden the air coming out is not cold anymore. The fans are all working but the AC compressor is coming off. I'm guessing it may need a recharge, but I'm confused. It still comes out ice cold when it works and if I move the switch around a few times it comes back on, ice cold. I'm almost thinking the switch could be bad but it could be coincidence. Any known issue with bad switches or other things to look out for? Otherwise the car runs fine, it on has 30K miles. It is 10 years old now so its prolly about time for a recharge. :shrug: Opinions/Advice? Thanks! :thumbsup:

 

[GMKILR9050]

Check in front of the condenser to make sure there arent any leaves or a peace of paper blocking airflow through it. Ive seen that happen, also, you could be 3-5 ounces low. I hate air conditioning problems!

 

[PJM99]

Yeah, i don't think there's anything blocking it but I'll check. I'll have to trouble shoot.

 

[Doug]

which switch are you moving? if its the hot/cold switch then it could be the blower plate. i forget the technical name for it but its the flap that directs hot or cold air out of the vents. usually only happens on high milage cars and the flap gets so gummed up it dosn't want to move and needs to be cleaned.

but as i said, i've only heard of it in high milage vehicles. it requires pulling the dash apart to clean.

Dunno if that is your prob, but its possible, i guess.

 

[CJK440]

If the compressor clutch disengages then its not ductwork related.

Most likely you need a boost of refridgerant. There is a low pressure switch that turns off the compressor clutch when it gets below a certain pressure. The lines have a certain amount of pressure with the A/C off and the pressure drops when the compressor runs.

So what is happening is your compressor turns on, the pressure drops below the setpoint and shuts the compressor down. The pressure builds and turns the compressor on. etc. etc.

These cars should have R-134a right? Just go to your parts place and get a cheap charging kit with a cheap guage and top it off yourself.

 

[LSWHAT??]

^^^^^ What he said!

That is exactly what mine was doing, and I topped it off and it works great, although I rarely use the AC.

 

[Redhot91gt]

If the compressor clutch disengages then its not ductwork related.

Most likely you need a boost of refridgerant. There is a low pressure switch that turns off the compressor clutch when it gets below a certain pressure. The lines have a certain amount of pressure with the A/C off and the pressure drops when the compressor runs.

So what is happening is your compressor turns on, the pressure drops below the setpoint and shuts the compressor down. The pressure builds and turns the compressor on. etc. etc.

These cars should have R-134a right? Just go to your parts place and get a cheap charging kit with a cheap guage and top it off yourself.

Yup sounds like whats happening in this case. :thumbsup:

 

[PJM99]

yea must be low, thanks guys

 

[03redfirevert.]

Just be sure to get the 134a WITHOUT the sealer, you bring it to a shop and have a/c work done, and you put sealer in the system,it will ruin they're $4000 recycler,not a good thing,basically a mechanic in a can,like the headgasket sealer,
quickfix now but WILL cost you more in the long run