how do you do a diagnostic on the a/c in a 1990 when i turn the key on the selctor light flishes for a min or 2

 

I'm confused... What does the selecter light flashing for a minute or 2 have to do with the AC diag??? The AC diag is at:
http://www.idavette.net/tech/c4diag.htm

 

well i want to see why it is flashing and thanks

 

well the code said Temp Door Motor Circuit Fault does any one have one for sale

 

I have an 85 coupe. Until a few months ago my A/C was working great. I didn't any troulbe with it, but, I didn't leave well enough alone. I put a hole in my evaporator trying to mount a msd box. I replaced the evaporator coil. Here's my question .....is there any other parts I need to change to accept R134. Or can I simply do the retro change (I have a kit with R134 fitting)from R12 to R134 of cousre after I have the system vacum

RSSSHEN VETTE

 

You always replace your accumulator when you convert.... I'd replace all your O-ring also... Use Santech MT-2541 which is sold at Autozone... Flush it, and replace the orifice tube...

 

My AC was repaired last week. They charged me $150 to evacuate the system as an extra. There were disconnected hoses so I thought it was essential to do this. Why would a shop even ask the question?

Anybody have a quess on this

 

I did my 91 two months ago, and I replaced the accumulator along with all the O-rings. Also I replaced the orrifice tube which is in the evaporator. Something else you may want to consider, is taking it to a shop to have them evacuate the system, and recharge, ($125 here in Rochester, NY). I know it is a little more expensive, but well worth it. Mine blows ice cold with the 134A, and I don't feel a difference as some people say the R12 is colder

 

You suck all the air out of it - assuming it was exposed to the atmosphere - because refrigerant and air don't mix. Leave it in there, and you won't have enough room for the refrigerant - the volume is fixed. And whatever refrigerant is in there will have a much higher operating pressure meaning that the refrigerant is boiling (and absorbing heat) at a much higher temperature so it's not as cold as it could be. Of course if the pressures get high enough, it can blow a hole in the hood, but hopefully the switch that cuts power to the compressor under those circumstances is in good shape and working. Finally, the moisture that's in the air is also absorbed by the lubricant and when that happens, it doesn't lubricate very well so the compressor craps out. I can't imagine a shop wanting you back next week bitching about a broken compressor, so the good ones make sure they do what they can to prevent that (and it's why some of them refer to the Walmart conversion packages as "Death Kits."). Oh, and you replace the Accumulator because the drying agent inside of it doesn't last very long if it's exposed to a lot of air and when it breaks, it turns into nastly little chunks that destroys the compressor and plugs everything up leading to a $1200 to $1500 rebuild - which for some years and makes is just the cost of the new parts.