How JustAnswer Works:
  • Ask an Expert
    Experts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
  • Get a Professional Answer
    Via email, text message, or notification as you wait on our site. Ask follow up questions if you need to.
  • 100% Satisfaction Guarantee
    Rate the answer you receive.
Ask ASE Master Tech 35yrs Your Own Question
ASE Master Tech 35yrs
ASE Master Tech 35yrs, ASE Master Auto Tech
Category: Car
Satisfied Customers: 2095
Experience:  ASE Certified since 1972,Master Auto tech,Heavy Truck Tech, foriegn and domestic
Type Your Car Question Here...
ASE Master Tech 35yrs is online now
A new question is answered every 9 seconds

Air suspension compressor on my 91 lincoln town car is not coming on

This answer was rated:

The air suspension compressor on my 91 lincoln towncar is not coming on

ASE Master Tech 35yrs :

Glad to be of help. Have you checked the switch in the trunk? If the wires are getting hot, it sounds like something is shorting out. The junk yard compressor may be bad.

ASE Master Tech 35yrs :

I'm switching to Q&A format to be notified of your response.

Tell me what led up to this problem. Has any work been done previously?
Customer: replied 6 years ago.
The wires were not getting hot with my original compressor. A few months ago I had a short in the wire that goes from the fuse box under the hood to the compressor and I changed that and it worked. I did blow some fuses for a few days but it stopped. I checked to make sure the switch in the trunk was on and it was. On Wed. of last week The compressor worked going to work but when I came out and headed home, it did not and hasn't since. I do have a leak in one of my air shocks and have not been able to replace it yet.
Having a leak will cause your compressor to run continously and eventually burn out your compressor. You need to get the leak fixed first. It is obvious that your junk yard compressor is just that, junk.
Customer: replied 6 years ago.

When I changed the compressor, what would cause the wires to get hot? Well, being on a limited budget..$32.00 is better than $150.00. But then, you get what you pay for.

A short to ground will cause the wires to get hot or a locked up compressor.
Customer: replied 6 years ago.
Could I then have a bad ground? If the compressor is locked, would it make a humming type sound or no sound at all?
Yes. The root cause of wires getting hot is excessive resistance. Poor connections can cause this. If a compressor has been sitting for years in a junk yard, corrossion can build up.
If you still have your receipt, I would go back to them and get a repacement at no charge.
Customer: replied 6 years ago.

On the original compressor the wires did not get hot. Does this rule out a bad ground? Now when I replaced the short before, I cut the wire but I did not have a sodering iron and I used crumps. Could this be the issue...bad connection? I would like to rule out all possibles before I get another compressor.

This is a possibility but if the wires you crimped on were clean and connector was new and the connection secure, it is doubtful that this is the cause. I have no way of knowing how well you crimped the connection. Make sure all your connections are clean and secure. You can test the compressor very quickly by hooking it direct to the battery and attaching a pressure gauge to the outlet port. If your leak that you say you have is greater than the output of the compressor, it will do no good replace it until the leak is fixed.
Customer: replied 6 years ago.

"You can test the compressor very quickly by hooking it direct to the battery and attaching a pressure gauge to the outlet port." Can you explain how I do this?

You will need some wire with alegator clips and a pressure gauge and some winshield wiper hose. You will also need a connector that has a short piece of the air line attached to connect to the outlet port. Attach gauge to the line via windshield wiper hose and Attach one wire to positive terminal and one to negative terminal of battery via alegator clip. It not quickly getting all the preparations together but quick to test. It would be much quicker to get a replacement since you know this one does not work for you. Compressors either work, or they don't. If the air is leaving the system quicker than it's going in, your problem will still not be solved.
Customer: replied 6 years ago.
Where do I connect on the compressor? Do I attach both clips to the purple/orange wire of the compressor?
No, you need another wire to ground the compressor.
Customer: replied 6 years ago.
I think I have it. I leave the compressors connected as normal, that a new piece of wire attach to the compressor and then attach the clips to that wire and then the battery. Next do I start the car or leave it off?

Leave it off. The purpose of the alegator clip is to be able to remove it quickly in case of a short. Here is a picture of your compressor.


If your compressor is making noise when turned on, it's working, if the wires are getting hot, there is excessive resistance in the circuit.


Here is how your leveling system works:


A Lincoln Town Car's air suspension uses a small, separate air compressor under the driver's side left fenderwell, and air lines run to the air bags. On top of each air bag is a electrical valve that serves as a relief valve that allows air to be exhausted when activated. The valve senses the amount of air pressure within the air bag to keep both sides equal. These valves are operated via a leveling sensor that is attached to the body of the car and to the rear axle by a movable arm. When the rear of the car drops because of an increased load, the arm is pushed up, turning on the air compressor and filling the air bags to level the car. When the load is removed and the arm moves down, indicating that the back of the car has risen, the sensor opens the valve on the air bags and allows air to escape, lowering the car.

Customer: replied 6 years ago.
Now another variable..the leveling sensor. Could that be bad giving a false reading and not activating the compressor when the rear gets too low?
Yes. Try another one from the same place you got the compressor and have them check to see if the compressor you bought from them is good. It could also be a problem with the multi-function switch (module).
Customer: replied 6 years ago.
Could you send me a picture of the sensor and it's location? The last time I had an issue I got a compressor from the same place and it was bad. What are the odds? I have gotten other parts for my car adn my son's car and they have worked fine. This part apprears to be the exception!

I"m sending you a link that should help you with your problem. It is quite informative.



Height sensor: under the car from suspension to frame

Control module '90 - '94: Right side of trunk behind trim panel

ASE Master Tech 35yrs and 11 other Car Specialists are ready to help you
Customer: replied 6 years ago.
Thank you. I will do your suggestions and see where I am at.