2003 GMC Envoy 6 cyl Two Wheel Drive Automatic ~60000 miles
This is an odd problem for me in that the problem is not persistent. We have the load-leveling package with the air suspension. What is happening is that we'll come back to the vehicle after it's been sitting, and find the rear air bags completely deflated, with the rear end completely lowered. But after we put the keys in the ignition, it will inflate just fine and ride just fine. The compressor doesn't have to turn back on (to re-inflate) while we're driving it. It seems to hold air.
Now the odd part. We can leave the vehicle sit for DAYS, and it doesn't deflate a quarter inch. Yet other times, we can come back in a hour and it's completely deflated. I have NEVER seen, or heard it losing air. But it obviously does, as I said it can completely deflate in an hour. Originally, this happened once or twice a week. Now, it's about 5-7 times a week, so it does appear to be getting worse. I'm thinking of putting a webcam on it overnight so I can see if it's a gradual or fast dump of pressure.
I can't understand what could be wrong where it would retain air indefinitely sometimes, but other times completely deflate, like the system purged air.
I've done a quick check for leaks, and didn't find anything, but didn't have much room under there. I plan to lift it and try again. But I need more ideas.
Thursday, April 24th, 2008 AT 9:26 PM