Anyone here a car AC tech? This is driving me nuts, I have a 1999 Isuzu Rodeo that I've been trying to fix the AC system on for the past month and have already wasted so much money. Originally it had a weak AC that would only go could if I pressed the accelerator which I diagnosed to a weak compressor. Now I've replaced the AC compressor, evaporator, control valve and dryer and it's not getting cold at all. I've followed the procedure of flushing it out and then running a vacuum to boil out any moisture.
This is the readout on the manifold gauge, the low pressure line is high while the high pressure line is low. The compressor engages fine and I've already wasted $50 worth of AC coolant and it's still not getting cold with the same gauge results like this. What the hell is going on??
>>950126
This is probably more of an /o/ sqt desu...
You more than likely though have a line leak somewhere...
>>950126
High low-side and low high-side is almost always a compressor but can be expansion valve. Check to see if anybody installed an aftermarket filter in-line those things fuck everything up (if they did it would be on the low-side before the expansion valve.
its the expansion valve most likely. this is what causes the compressed gas to expand into a liquid. if theres a blockage the gas cant expand properly and wont become liquid and thus wont get cold
>>950306
does it still blow warm air even when you first start the car before it has a chance to warm up?
we need more info to diagnose from the gauges. whats the outdoor temp? whats the temp in the cabin?
>>950306
>But the compressor and expansion valve is brand new.
New things dont always work
>>950126
did you weigh the charge?
>>950126
You overcharged it. You already covered all the bases, the compressor comes on.. I've seen this dozens of times, someone fixed their ac for some sort of problem it still doesnt work. I evac the system, it's a pound or 2 over. Also, it sounds like your original problem was a slight undercharge. You replacing the parts you did didn't hurt anything tho (besides your wallet). Run the ac, put your hand somewhere on a low side pipe. Let a little out at a time until the pipe gets ice cold. Or take it somewhere they can evac it and charge it to the specific weight so you don't rip a hole in the ozone layer and personally cause global warming.
I am betting OP didnt have the system evacuated prior to recharging... and that air in the system fucked up something....
I'll put my money on the rad leaking - you've replaced everything else OP - put a new radiator on. They take a lot of stone chips and shit from the road mostly being placed at the front of the engine.. and the fins are fragile.
>>950126
just throwing this out there, but you didnt put the compressor in arse-about did you?
Check that your condenser fan is spinning
you may only be getting cool air while accelerating because the condenser is being cooled only from wind from acceleration and not with a fan like its supposed to
At this point your problem is 100% an issue with the high/low side levels. Take it in and have a dealership set the correct levels and you'll be good to go. Some might even do it for free if it's overcharged since they'll get to keep the extra coolant when it's all said and done. They have a machine that pulls all the coolant out and holds a vacuum on the line for a bit. Then if the pressure doesn't change when under vacuum they'll know there is no leakes in the system. Once that's good the machine pumps the correct amount of coolant back in the system. Any leftover unused coolant is stored in a propane looking tank thing and used for the next customer. AC's high/low side are pretty picky and the levels have to be exact. Even a slight variation will throw the whole thing off.
>>951168
/thread
>>950126
An hvac friend told me it may be low on refridgerant. I would pay someone look at it and tell me what went wrong, then do the repair myself.
