Cold A/C runs out after about 15 minutes of driving
#11
The magnetic force from the coil gets weaker when it is hot (because the resistance of copper wire increases with temperature), and if the gap is marginal the clutch will not always engage after it heats up. At this point I'd just take some shims out. You should be able to do it with the compressor on the car if you jack up the left front (support it securely), then remove the wheel and the plastic inner fender.
#13
Another update: Yesterday it was rainy and about 78 degrees outside. The A/C blew cold whenever I drove anywhere all day long. Today it is cool as well, around 75 this morning and it blew cold all the way to work. It appears I only have the problem when it is hot outside.
I've isolated the problem to something to do with the compressor and only when its hot. Even in 90 degree weather when I first start the car it will blow cold air. It only lasts about 15 minutes then stops, then starts again randomly.
Any ideas?
I've isolated the problem to something to do with the compressor and only when its hot. Even in 90 degree weather when I first start the car it will blow cold air. It only lasts about 15 minutes then stops, then starts again randomly.
Any ideas?
#14
Just curious, do you plan to do any troubleshooting yourself or will you just eventually take the car to a shop? If you plan to do the troubleshooting, then you already have some suggestions. You should additionally hook up a manifold gauge set and measure refrigerant pressures on the high and low sides.
#15
I've taken it to a shop and their solution was to add refrigerent. That didn't solve the problem. Depending on what the problem is I might fix it myself or I might take it to a shop. Basically if it involves having to discharge the system I'll have a shop do it. If I can replace a part that doesn't require discharging then I'll do it myself.
I am pretty mechanically inclined and would prefer to do it myself if I can. The shop I took it to also recommended I replace the condensor at a bargain price of $446. I know the condensor isn't the problem because the issue isn't related to drive on the highway vs in town. It will all of a sudden stop blowing cold air at 70 mph, then all of a sudden start blowing cold air again.
Testing those connections on the compressor is going to be difficult, I can't reach my hands in there far enough to reach them.
I am pretty mechanically inclined and would prefer to do it myself if I can. The shop I took it to also recommended I replace the condensor at a bargain price of $446. I know the condensor isn't the problem because the issue isn't related to drive on the highway vs in town. It will all of a sudden stop blowing cold air at 70 mph, then all of a sudden start blowing cold air again.
Testing those connections on the compressor is going to be difficult, I can't reach my hands in there far enough to reach them.
#16
Testing those connections on the compressor is going to be difficult, I can't reach my hands in there far enough to reach them.
#17
I measured the distance between the pulley and the amature plate with a feeler guage and it is 0.019 in. That appears to be in spec. Today on the drive home from work it blew cold air the entire way. After I got home I turned the A/C button off. The clutch disengaged. I turned it back on and like the other day it did not re-engage. I took a long screw driver and with the engine running I lightly pressed in on the amature plate. When I did that the clutch engaged and the A/C started blowing cold immediately.
Thoughts?
Thoughts?
#19
I went ahead and removed the one and only washer shim that was behind the amature plate. The gap is now .005 in. I did some quick testing, started the car with A/C off and the compressor clutch was not engaged. Turned A/C on and it engaged, flipped the A/C on and off a few times to make sure it wasn't hanging on when it wasn't supposed to due to too small of a gap and it appears to be ok. I guess I'll drive it tomorrow like this and see how it does.
Last edited by DeanHensler; 07-22-2009 at 05:35 PM.
#20
I haven't been able to measure the field coil resistance? I took the black plastic inner fender out and still can't reach the top of the compressor with my hands. Is it going to be too dangerous to drive it with only .005 gap between the amature plate and the pulley on the compressor? I sure don't want to burn up the compressor.