Front end dropped, compressor will not turn on.

[spinningpedals]

I just scanned my 01 Allroad. The front end has dropped as low as possible, the compressor will not come on, Lights flashing. I have just put a new piston ring into the suspension compressor, worked better then ever, but now this. Is the G291 able to be pulled apart and serviced? Or is this problem more to do with the compressor itself? Oh and the compressor has be progressively louder.

Thanks in advance.


Address 34: Level Control Labels: 4Z7-907-553.lbl
Part No: 4Z7 907 553 B
Component: - 2C1A1 X031
Coding: 25500
Shop #: WSC 09999
VCID: 448D69845480FE3

3 Faults Found:
01772 - Signal from Level Control Pressure Sensor (G291)
27-10 - Implausible Signal - Intermittent
01400 - Suspension Level Control
11-00 - Control Limit Not Reached
01316 - ABS Control Module
79-10 - Please Check Fault Codes - Intermittent


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Address 55: Xenon Range Labels: 4Z7-907-357.lbl
Part No: 4Z7 907 357
Component: dynamische LWR D05
Coding: 00030
Shop #: WSC 02325
VCID: 040DA98414003E3

[Ixomeneus]

Sounds like it's probably the compressor itself. The biggest telltale is the fact that it's gotten louder. The 01772 G291 code *can* be one of those translational codes for a bad compressor as well since it doesn't have a dedicated code for failure.

As far as servicing, the G291 valve assembly isn't repairable. It's going to take a new replacement and I think they run roughly around $260ish I believe.

The 01316 ABS Control Module is also a transitional code since the J197 (I believe or the other level control module) is reporting an issue to the ECU.

I'd start to check out the compressor first then probably troubleshoot the G291 assemblage. (i.e. check hoses, etc).

Oh, and check to see if the compressor comes ON/OFF at all through VCDS on the graph log. I think it's programmed to be limited to like once every 2 mins due to temperature restrictions? Watching the air pressure in reservoir (above 4 Bar I think) would help.

Hope this helps a tiny bit.

[spinningpedals]

Thank you for your insight. I've found the 40 amp atc fuse has blown. I replaced it, turned on the car, activated the lifting cycle. Then the fuse popped right away. So tomorrow afternoon I'll be removing the compressor and inspecting it. Worst case scenario I'll find a way of supplying air to the suspension system so I can get out of our land lords lower driveway. Not a big task normally but I only have about 2.5 inches between the allroads down pipes and the ground. The rear is a tinny bit higher

At this point the car will be put out of service for a few months as the wife and i have just signed the papers to first house and take possession on the 20th of sept. Plus our baby is due on the 19th of sept. Gawd am I ever excited and nervous.

[Incrementalg]

Thank you for your insight. I've found the 40 amp atc fuse has blown. I replaced it, turned on the car, activated the lifting cycle. Then the fuse popped right away. So tomorrow afternoon I'll be removing the compressor and inspecting it. Worst case scenario I'll find a way of supplying air to the suspension system so I can get out of our land lords lower driveway. Not a big task normally but I only have about 2.5 inches between the allroads down pipes and the ground. The rear is a tinny bit higher

At this point the car will be put out of service for a few months as the wife and i have just signed the papers to first house and take possession on the 20th of sept. Plus our baby is due on the 19th of sept. Gawd am I ever excited and nervous.

Congrats on the house and baby! Same for us 18 mos ago...new house and baby within days of one another. It didn't take long for me to decide to sell my ar. Too much to do to babysit my favorite, but problem prone ride...lol.

[awdjunkies]

Thank you for your insight. I've found the 40 amp atc fuse has blown. I replaced it, turned on the car, activated the lifting cycle. Then the fuse popped right away. So tomorrow afternoon I'll be removing the compressor and inspecting it. Worst case scenario I'll find a way of supplying air to the suspension system so I can get out of our land lords lower driveway. Not a big task normally but I only have about 2.5 inches between the allroads down pipes and the ground. The rear is a tinny bit higher

At this point the car will be put out of service for a few months as the wife and i have just signed the papers to first house and take possession on the 20th of sept. Plus our baby is due on the 19th of sept. Gawd am I ever excited and nervous.

Congratulations on both, your house AND your new bundle of Joy!!!

[spinningpedals]

Oh thanks for your kind words guys, Yeah I expect I'll keep my Allroad another 10 or so years( already had it for 5 years).. I just love this car.

A positive update for the compressor. After removing the compressor from the car I pulled it a part to see whats the matter. I found the bearing for pressed into the connecting rod/piston assembly had seized causing excessive current draw, hence the reason for blowing the 40 amp Atc fuse. So after having difficulty removing the bolt that fastened the connecting rod to the crankshaft.. I decided to speed things up and break out my impact gun... Wrong move, I snapped the head off the bolt, had to drill out the remaining portion from the crank shaft. To later find that the bolt was a left had thread( reversed thread). After finding it seriously difficult to locate a left hand threaded bolt, I gave up. Re-threaded the crankshaft to accept a standard right hand threaded bolt.

Located a new bearing from a local supplier( the original was: BRS 6002), pressed that into the connecting rod. Assembled the compressor, and powered it up for a 5 min. trouble free operation I thought I'd test this lil gapher out and test how high of pressure i cant reach before it gives out and started to sound as if it was labouring too much. 200PSI. was where i wimped out and pulled the compression tester off the compressor.

So now the hunt is on for some new desiccants for the dryer. Seems trying to locate a small amount of this stuff isn't so easy. So far I've found prices of $60 for 2 liters and up to a box for a $130... considering this compressor only requires a high ball glass worth... I'm still searching.
Apparently Acklands Grainger has smaller amounts for $30, I'll be calling them tomorrow.
Question, is there an easy way to post pictures on the forums with out having some website?