AC question
AC question Hi there,
I have a 01 Z28 A4 all stock with 50K miles.
I noticed that whenever I drive for more than half an hour or so without turning off the engine, cruising, the AC will stop blowing cold air and it will just blow air.
This does not happen when I drive for short distances, or when I turn on / off the engine multiple times, only when I'm cruising at fixed speed for long distances.
What could be the reason?
Thanks for the help.
I have a 01 Z28 A4 all stock with 50K miles.
I noticed that whenever I drive for more than half an hour or so without turning off the engine, cruising, the AC will stop blowing cold air and it will just blow air.
This does not happen when I drive for short distances, or when I turn on / off the engine multiple times, only when I'm cruising at fixed speed for long distances.
What could be the reason?
Thanks for the help.
Hi there,
I have a 01 Z28 A4 all stock with 50K miles.
I noticed that whenever I drive for more than half an hour or so without turning off the engine, cruising, the AC will stop blowing cold air and it will just blow air.
This does not happen when I drive for short distances, or when I turn on / off the engine multiple times, only when I'm cruising at fixed speed for long distances.
What could be the reason?
Thanks for the help.
I have a 01 Z28 A4 all stock with 50K miles.
I noticed that whenever I drive for more than half an hour or so without turning off the engine, cruising, the AC will stop blowing cold air and it will just blow air.
This does not happen when I drive for short distances, or when I turn on / off the engine multiple times, only when I'm cruising at fixed speed for long distances.
What could be the reason?
Thanks for the help.
have you ever had any AC related service?
i'm not an ac expert but first thing to verify is the radiator is clean and the condensor (little AC radiator in front of main engine radiator) is clean. hose it down and make sure it's clean.
after that, you would need AC pressure gauges. you can measure the static pressures on the low and high side with the engine having been off for 10 min or more to see if you're low on refrigerant. if your below 50 psi at 60F ambient temp, below 70 psi @ 75F or below 100psi at 90F then you're low on refrigerant and need a charge.
if that checks out then you may have to measure service port pressures with the engine running. the high pressure side liquid line from the compressor through the condensor (radiator) to the expansion device should be warm/hot all the way to the expansion device. if there's a temp drop that you can feel then there's a restriction that needs to be cleaned out, and you'll need to determine where the debris came from and if it's metal it's probably your compressor on it's way out. same would go for all the low pressure side lines, anywhere you can feel an abrupt temperature change on the line there's a restriction that would need to be flushed out. and i think there's a filter on the expansion device that's either serviceable or replaceable. hope that helps.
http://www.familycar.com/ac1.htm#ACCUMULATOR
i'm not an ac expert but first thing to verify is the radiator is clean and the condensor (little AC radiator in front of main engine radiator) is clean. hose it down and make sure it's clean.
after that, you would need AC pressure gauges. you can measure the static pressures on the low and high side with the engine having been off for 10 min or more to see if you're low on refrigerant. if your below 50 psi at 60F ambient temp, below 70 psi @ 75F or below 100psi at 90F then you're low on refrigerant and need a charge.
if that checks out then you may have to measure service port pressures with the engine running. the high pressure side liquid line from the compressor through the condensor (radiator) to the expansion device should be warm/hot all the way to the expansion device. if there's a temp drop that you can feel then there's a restriction that needs to be cleaned out, and you'll need to determine where the debris came from and if it's metal it's probably your compressor on it's way out. same would go for all the low pressure side lines, anywhere you can feel an abrupt temperature change on the line there's a restriction that would need to be flushed out. and i think there's a filter on the expansion device that's either serviceable or replaceable. hope that helps.
http://www.familycar.com/ac1.htm#ACCUMULATOR
