AC Hot Air !!Help!! 92 q45

[ladyq45]

I have a 92 q45 when I got the car AC worked fine very cold. had car 2yrs .last year AC gave out hot air. took car to mechanic he put new fittings on for new freon ? then said he cannt recharge because I need new expansion valve, no leaks , new valve cost with labor $500 I said no didnt trust him. so went to jiffy lube got recharged still not hot air they didnt charge me said he filled freon so its not that..well I turned on AC this year and was getting cool air not cold..did for a couple of days.it was 100 degrees outside .then hot air started and burning smell like wires. Any suggestions?? Thank-U

[DAEDALUS]

The last thing you want to do is convert the type of refrigerant used. The old stuff (R12) is 10x more expensive, but it doesn't need new parts, or a complete system flush, and it works better than the new stuff (R134a). Plus there are no contamination issues. So Jiffy Lube filled the system with R134a? This could be a big problem unless the system was completely flushed out to get the old oil out. The burning smell is usually the belt burning, which in indicative of either a bad tensioner or a bad compressor, or both.I'm sorry, but it doesn't sound like there's a cheap fix to be had. The system will need a complete flush if it hasn't yet had one, plus a new drier, plus whatever is broken.

[ladyq45]

ok thanks for the quick reply..but do you think it could be the expansion valve like I was told first? or because of burning smell its compressor? And what about the fuse link underhood could that be it? I tried to take out but it wont move .What is that for? I notice it is loose not as tight as others. tried to pry it open with flathead screw driver but it wont pull out. do I need to change AC belt or check it for tension? Thanks again

[maxnix]

Give us an idea of what refrigerants and lubricants were used to recharge your unit. If they added R134a into an R12 system, you could need a whole new unit.

Best thing to do is to take it to an experienced AC specialists, not a mechanic who may do recharges on the side.

[DAEDALUS]

It could be the expansion valve, if that's what his diagnosis was from reading the pressure gauges. But the burning smell is not caused by the expansion valve.The fusible links are bolted in at the bottom. Don't pry off the plastic cover.You can check the belts for glazing, turn the idler by hand to check its bearing, and retension the belt. If it's a belt/idler problem, that would be good, except the potential contamination issues still need to be addressed.