I have a 2003 Ford Crown Victoria with air suspension on the rear. First, I thought the bags developed leaks, because the compressor would go on just about every time I get in the car to drive. (Before this, the compressor would go on once every few days.) But then, I also heard hissing air from the place where the compressor and other related stuff are. So, to check whether the bags are holding air, I turned off the air suspension switch in the trunk, and the car seems to hold ride height quite well. It may be a week or more before I notice any change in vehicle height, which means, THE BAGS ARE HOLDING AIR. So, it seems the air suspension system somehow became so sensitive that it will inflate every time someone gets in, and it will let air out when he engine is turned off and people get out. I tried disconnecting the battery, which I assume will reset air suspension system, but it seemed not to work. When I turn on the air suspension system, it does inflating/deflating cycle again. I know there is a ride height sensor in the back, but from what I can find on the internet, defective ride height sensor would make the car ride too high or too low, which indicates the sensor is not able to sense the ride height. But with my car it seems overly sensitive. Is it the ride height sensor or is it something else?
Which is EXACTLY how it is supposed to operate.
Have you owned this car for 19 years? Or did you just buy it?
+1
Back in the days when I drove a Fleetwood limo as a second job, as soon as I got into it in the morning, I could hear the pump working. When passengers got in, it would work for even longer. When the passengers exited, it released some of the air.
Is this new?
I bought the car in 2011 with about 50,000 miles on it, and now it has about 140,000 miles on it. As soon as I bought it, I replaced the air suspension compressor dryer. So, I know where the air compressor is, and I know when it goes on to inflate the rear. Until about 6 months ago, the compressor would only go on once a week or so. I know it went on nearly every time I fill up the tank from 1/4 to full. It never went on when one extra person got in the passenger seat. Now, I drive with the air suspension off. About once a week, I turn the air suspension on, and it goes on for about 10 seconds, which is how long it would go on in the morning if I left it on all the time. I tried to measure with a tape measure how much the car lifts at the rear tires when the compressor goes on for about 10 seconds, there really is no noticeable difference. Does that sound normal?
I guess I am missing something here . Why turn the leveling system off and on ? Also don’t many people just replace the air ride system with normal struts ?
OP, is the hissing noise new? If it is, there may be a leak in that area contributing to the problem.
Roger,
I have a 2007 GMC with air suspension, same issue as you. Never noticed the pump working, until about a year ago. Never sits low or high , but the pump seems to cycle often. I feel your pain that I do not want the pump running as much as it does. But really there is no problem with the system, just my OCD noticing it more. If you can, ignore it and be happy that it is working correctly. Be thankful it does not give you the “Carolina Squat”!
Why are you doing this? Are you annoyed by the compressor noise? Are you trying to prolong the life of the compressor? You are subverting the way the manufacturer designed the system to work.
I’ll bet a stack of $20 bills the system is leaking just enough to cause the compressor to cycle a bit more than it did at 40K miles. And that includes the back-flow valves in the compressor. I’d also bet the isolation rubbers installed to quiet the compressor have degraded to the point it makes the compressor more noticeable to you and now you are obsessing about it so you notice it more.
You have 4 options as I see it… 1) Leave it on all the time the way Lincoln designed it. 2) Keep switching it on and off. 3) Replace the system with steel coil springs or 4) Replace the air springs and every line and fitting to those springs so the entire system is renewed except the compressor…and then the compressor will need to be replaced as well!
if you are hearing hissing, then something is likely leaking. are the lines/hoses accessible enough to spray them down with soapy water to try to find a leak? This may be as simple as a fitting leak, or a line rubbing through.
I have air bags on the rear of my truck, that I have to take the lines loose when I remove the bed to do a fuel pump (I’m getting good at it though. Thanks GM…) One time I didn’t get one hose all the way secured and had a bit of a leak there. soapy water and a little bit of paying attention to bubbles helped me figure it out.
Odds are there is a small leak. With age the air bag rubber will develop dry rot (just like tires) around the fold of the rubber.
The height can affect the fold and a leak can at times be a bit hit and miss. If it’s not leaking after roughly 20 years I would be utterly surprised.