bonestock2000v6

I have a 2000 Ford Mustang v6 5 speed with a 212000 miles. The engine runs great with the A/C off. Plenty of power and pretty smooth idle and driving. However, when I turn on the A/C the car seems to have a death wish. It blows very cold air constantly and doesn't surge or seem to have sudden clicks on and off. There is a constant and frustrating power loss at all times with the A/C on. It becomes a difficult job not to lurch or stall the car when starting from a stop and I have much worse gas mileage. I have driven many automatic cars and several manual cars and none have had a power loss even close to this. I understand that there should be a small power loss with the A/C on but mine seems to hardly run at all. Advice?

Archion

At idle does it seem to idle too low with the air on? The IAC should kick up a few rpm's to compensate for the A/C.

bonestock2000v6

No it seems to idle correctly with the a/c on. I have cleaned the iac and it seems to work properly

bonestock2000v6

Also from my observations is seems that the clutch does not cycle on and off properly. It constantly spins while the A/C is on

Archion

with the a/c on, it is supposed to spin. constant cycling is actually a sign of low refrigerant or a bad pressure switch. At most every few minutes with no load, fan on low. it works off the low side pressure. does it disengage when you turn the a/c off? Also, while the a/c is on. try unplugging the low side switch on the accumulator and see if it goes off.

bonestock2000v6

Yes when i switch off the a/c it does disengage. How noticeable is the clutch disengaging during normal operation? would i see it stop moving for a second? or is it a very quick thing? I will try doing that. Where is that switch?

corker

Check grounds - focus on G100 ground connection at Left Front of the engine compartment. That ground is for the constant control relay module (CCRM) that handles the A/C clutch relay (among other things) and is shared with MAF sensor. Trace grounds back from G100 to ensure all wiring is good and no broken or corroded wires. If the compressor coil doesn't have a good ground it can be searching anywhere to ground and cause a lot of weird problems.
Good Luck

bonestock2000v6

Thanks! Looks like I've got some wire hunting to do today

corker

Abbreviated wiring diagram of A/C

bonestock2000v6

Oh wow! That'll help a lot. I'm about to go out of town though so I may not be able to figure it out til next Thursday or Friday