Cadillac Repair: 1990 STS rear struts and exhaust manifold, air ride suspension, air struts

Question
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Followup To
Question -
I have a 1990 SeVille STS with rear air ride struts. Is it possible to convert this system to a standard coil-over design? It would be nice if I could use exsiting parts from another year/model to do this? Any help you can provide will be great. Also the front manifold is cracked and I am having trouble locating a good used one. Do you know if the 4.6L manifolds will work on the 4.5L engines?

Thanks,
Johnnie Watkins
Roanoke, VA
Answer -
No you cannot and should NOT alter the air ride suspension system on the vehicle. This will cause all sorts of problems with fault codes illuminating your air ride suspension light and your BCM computer light on the dash.

There is no such light on my dash board. My rear strut system is two air struts, one compresser unit and a crude looking designed switch that mounts to a bracket with an arm that attaches to the lower control arm on the drivers side. The arm has been broken for quite some time now and there is a leak, or bad compresser, as well. I have ran the OTC Gynsis on the vehicle several times and have never pulled a code pretaining to the air ride.

Answer
Your correct they did not incorporate the ride height circuitry into the computer system until the mid-90's vehicles.

Yes, You ca go ahead and convert the air shocks if you wish. However once you put a heavy load in the trunk the car will not automatically level out as the back end will be down and the front end will be up.

As to the manifold compatability your best option would be to call a salvage yard and ask. If you ask the dealer's parts department he is only going to show that they have 2 different part numbers and he has no way to tell if they will swap out.