Hi Glenn, I hope that your reply to this is "oh, that's an easy one"
For just short of a year now we've been fighting this one on and off. The problem is that the front half of the air ride system on my wife's '97 Lincoln Mark VIII may or may not inflate. Currently,it is refusing to inflate and the front end is completely all the way down. About a year ago the front end began to deflate whenever you turned off the car. Sometimes it was quite quickly and other times it was sometime over night. Upon startng the car the front half would reinflate with no further problems until you shut it off. I thought it was just a slow air leak and with the car running, the compressor would keep it pumped up. However,later on and quite by chance I discovered that after turning off the car you can hear a click like that of a light switch somewhere under the hood and then the sound of escaping air and the front system completely deflates. But, again, it would reinflate after starting the car. At a point in time later on it started to refuse to reinflate. At this point, the compressor would run (it's new) and the rear half would rise slightly from its normal hight. When the compressor would finally shut off, the front end would still be down and the rear would settle to the proper ride hight. So, I took it to the dealership and they plugged their machine (a computer of some kind I suppose)into the air ride system and ran it through a series of commands and of course the system preformed flawlessly including reinflating the front end. The end result was that they had no clue as to what was wrong with the system as it preformed all tests perfectly. Over the next several months I went through the same thing 3 more times at the dealership and always the same result...no one has a real clue. They did offer a guess and said that one of the computer boxes is malfunctioning but offered no guess as to which one. Apparently there is one behind the right front kick panel and one under the back dash in the trunk. In July after the last trip to the shop and with the system fully inflated I turned the system switch to off. The system stayed inflated with no air leaks until late December when I noticed the car had settled about 1/4 down at both ends. I guessed that the cold weather had shrunk the seals and was letting air slowly escape. So, here goes nothing, I turned on the system and I was in luck as all 4 corners reinflated to the proper hight. At the end of Feburary I noticed it was slowly settling again in the now super cold weather. So I turned the system switch to on and the compressor kicked in and reinflated the rear half, but the front half didn't move and stayed at the same position it was in at about 1/2 to 3/4 inflated. Like a blockhead that I can be, I shut the car off without first turning off the air ride system switch...big mistake! I heard the familiar click sound from somewhere under the hood and all of the air was released from the front end almost putting the front bumper on the ground. It now refuses to reinflate.
I'm at my wits end and I don't want to spend a ton of money going back to the dealership for another round of "I don't know what's wrong with your air ride system, but here's your bill anyway". If I have to replace one of the computer boxes, I want to replace the right one the first time as they're expensive. Can you tell me what's wrong and what I need to do to repair it?
Also, I was told that there is an air valve somewhat like a tire valve stem someplace in the air lines that I can use to pump up the system in case of an emergency. Is this true, if so where will I locate this air valve? And what is the correct air pressue?
By the way, since you are picking up the reply for Brian, is it safe to assume that you know each other?
Regards, and thanks for you help,
Ed Miller