A/C Random Cold then warm psi drops

[HellRazor35]

2007 e70 3.0 w. Adapt Drive.

Vin: 4USFE43517LY78582
Chassis: E70
Model: X5 3.0si
Engine: N52
102k

This is my daughters car and she is at college and I was not able to get the A/C Compressor replaced before she left. Had to do other maintenance before it was shipped and ran out of time
- Oil cooler gaskets
- Valve Cover
- Coils
- Water pump
- Thermostat
- Oil change
- Transfer case fluids
- Tranny fluid


Original AC Compressor failed.
JBBF [JBBF70] | A72F: Compressor clutch

Call the local dealer in Michigan and they were fine if I sent the parts with that they would install them as getting parts has been sketchy as of late.

So the BMW Dealer is replacing with a new A/C Comp from FCP (was not happy that their tension belt tool did not work on the face.)
- A/C compressor
- A/C Pressure Sensor
- Boltz
- Stretch Belt

It works great for about 10-15 mins then starts to blow warm air. The PSI drops, the compressor is engaging where the old one would not engage. BMW Dealer suggested that the new compressor is defective

Called FCP and they are sending out a new A/C Compressor to the dealer, there are no error codes not where initially I was getting

They said nothing else comes up in codes ???


Thoughts? Heater valve? Condenser?
I dont have much experience with AC systems I understand the basic concepts but not everything in the e70 with adapt drive and dual zones

Also say a AUC Sensor code but that should not have any relevance to the issue
JBBF [JBBF70] | A6CF: AUC sensor

Was looking back at old scans that I did prior to maintenance and these showed up in the logs not sure they are relevant. Believe these are for the senor in the rearview mirror?

KLIMA [IHKA70] | E723: No message (condensation sensor, 0x2D1), receiver integrated automatic heating / air conditioning system, transmitter roof function centre

KLIMA [IHKA70] | E729: No message (automatic air recirculation control sensor, 0x2D0), receiver integrated automatic heating / air conditioning system, transmitter JBE

Pretty sure everything is set to cold in the iDrive as I looked at this prior to shipping the car


Thoughts? Is the compressor diag right or are they just part hanging?

[andrewwynn]

Variable compressor stops compressing it's not uncommon. Rare when new but new ≠ fixed.

When people report this failure they usually report it will sometimes start working again later just not reliable. Odds are good the DOA diagnosis is correct.

[ard]

What a mess.


You did the diagnosis just based on codes?


Any chance you missed something and it really isnt the compressor? Or there was contamination in the system that wasnt flushed?



I find it amusing to accuse the dealer of 'parts hanging'.....when you paid them to hang your parts.

[HellRazor35]

To close this out ended up getting a new A/C Compressor from FCP and Dryer element. The dryer element was loaded with metal shavings, so either from the original compressor or the the new open that failed.