AC went out

[illusion88]

It's probably the compressor. I replaced it 5000 miles ago with one I got from a pick and pull. The day it quit, I could hear a noise related to the AC. It sounded like metal scratching or something. The interesting thing was, it was louder inside the car than when I had the hood up and my ear near the AC compressor....

Anyways, my question is, how can I diagnose a coolant leak from the compressor going bad? I don't have a vacuum gauge, would I need to buy one or is there another way? What are some ways to troubleshoot just the compressor assuming everything else is ok?

 

[exdeath]

Need a AC gauge cluster to check high/low pressure. I think you mean refrigerant and pressure instead of coolant and vacuum.

http://www.harborfreight.com/a-c-manifold-gauge-set-92649.html

If it's low, you have a leak. There isn't much else that you can do to diagnose AC, pressure is everything.

Other than that, just observations. Is it just not cold, or not blowing at all?

 

[Meghan54]

How well was it drained/vacuumed out when you replaced the compressor? Did you replace the drier at that time? Is the compressor engaging or not?

 

[illusion88]

How well was it drained/vacuumed out when you replaced the compressor? Did you replace the drier at that time? Is the compressor engaging or not?

Now the compressor isn't engaging at all. It would turn on but the air wasn't getting any cooler. Today, it just didn't turn on. I turn on the car, put it in neutral or depress the clutch, turn the fan on to a low setting (just so the noise of the fan and air doesn't interfer with me hearing the compressor) and then hit the AC. Nothing, nothing happens. The idle speed doesn't change, no additional sounds can be heard. The AC compressor isn't turning on. I checked the fuse, still good there. I am pretty sure that it's a compressor issue.

As far as the original replacement... A friend with an A/C Manifold Gauge set, maybe even the one pictured in the previous link posted, helped me out. We drained the original lines and then refilled to spec. I did not change the dryer.



Air is blowing, it's just not cold. I'm thinking with the new symptom that the compressor just gave out. It was from a Pick and Pull, and I didn't even pull it. It was on a shelf, how do I know it's history?

 

[Meghan54]

If the compressor was initially engaging and working after you replaced it and now it isn't, that's usually a symptom of too low a charge.

Of course, you didn't do yourself any favors by not changing the drier, which could very easily now be clogged by opening the system to air and not changing it afterward.

I'd try adding some Freon to the system first if you aren't going to replace the drier. And I'd use some Freon that has stop leak added to it, as well as oil.

I've also seen a low pressure switch go bad and give the same exact symptoms, which makes checking the system's pressure a necessity.

 

[Vette73]

Why did you replace the old one? Did it just leak or go bad?

If it went bad then you need to replace the dryer/accumulator, orifice tube, and the condenser in newer cars plus flush the lines out. If it was just leaking then you can keep the old condenser.

What’s happening now is you tried to take a short cut and its kicking you in the rear. Either do the job right and be happy or keep jimmy rigging it and enjoy throwing money and time at it every other weekend.

 

[kami333]

Some Autozones will lend out pressure gauges and pumps if you want to DIY.