Hi guys,
New not-100%-proud owner of a 2013 VW Jetta TDI. I knew what I was getting into emissions-wise, but there have been a couple other issues. The previous owner had an aftermarket rear wing installed, and it wasn't done well causing trunk leaks that I initially tried to stop by sealing the screw holes, but finally broke down and put a bead of sealant around the base of the wing mounts (works but not as clean-looking).
The second problem showed up as the weather warmed; intermittent AC failure causing short and then longer periods of warm air, even on max AC. The first garage diagnosed a grenaded compressor and wanted to do a full system replacement (essentially every pressurized component except the evaporator core). I got a second opinion and that mechanic replaced the expansion valve. The system has worked better since but not 100%, and the second garage now recommends a compressor replacement (but not a full system replacement); after reading up on the troublesome RCV, I'm guessing that's the real problem, and the improvement is due to the amount of fiddling the two garages have done which has loosened up whatever was sticking in the RCV.
The question for the floor is how to confirm this diagnosis? Here's what the second garage, which I trust more, has said:
* Loop oil looks fine; no discoloration (though that may just be due to the first garage replacing it as part of their AC service/diagnostic a few days earlier)
* No crud downstream; expansion valve replacement didn't find any deposits in the high-pressure line.
* Compressor turning and providing some compression as evidenced by some cold air output.
Replacing the RCV is a gamble; if it works I save about $750 on a full compressor replacement (and thousands more on a full system changeout), if it doesn't solve the problem I've wasted about $250 and still need a compressor replacement. It could also be the control unit, though the unit seems to be working internally, or the circuit running out to the RCV which may have an intermittent short.
New not-100%-proud owner of a 2013 VW Jetta TDI. I knew what I was getting into emissions-wise, but there have been a couple other issues. The previous owner had an aftermarket rear wing installed, and it wasn't done well causing trunk leaks that I initially tried to stop by sealing the screw holes, but finally broke down and put a bead of sealant around the base of the wing mounts (works but not as clean-looking).
The second problem showed up as the weather warmed; intermittent AC failure causing short and then longer periods of warm air, even on max AC. The first garage diagnosed a grenaded compressor and wanted to do a full system replacement (essentially every pressurized component except the evaporator core). I got a second opinion and that mechanic replaced the expansion valve. The system has worked better since but not 100%, and the second garage now recommends a compressor replacement (but not a full system replacement); after reading up on the troublesome RCV, I'm guessing that's the real problem, and the improvement is due to the amount of fiddling the two garages have done which has loosened up whatever was sticking in the RCV.
The question for the floor is how to confirm this diagnosis? Here's what the second garage, which I trust more, has said:
* Loop oil looks fine; no discoloration (though that may just be due to the first garage replacing it as part of their AC service/diagnostic a few days earlier)
* No crud downstream; expansion valve replacement didn't find any deposits in the high-pressure line.
* Compressor turning and providing some compression as evidenced by some cold air output.
Replacing the RCV is a gamble; if it works I save about $750 on a full compressor replacement (and thousands more on a full system changeout), if it doesn't solve the problem I've wasted about $250 and still need a compressor replacement. It could also be the control unit, though the unit seems to be working internally, or the circuit running out to the RCV which may have an intermittent short.
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