Check the fuse and fuel pump relay.

The fuel filter is under your vehicle, located directly in front of the fuel tank, in the fuel feed attached to the underbody.

Drop the tank. Haven't seen a cadillac with a access panel.

That all depends...When was your last alignment? Does the car pull or drift to one side a lot? The safe answer is YES, as long as you are willing to spend around $100 for front and rear alignment.

Any good aftermarket exhaust shop should be able to help.

Researched this a little bit apparently the chips in the cadillac keys can go bad when this happens the system detects it as theft, then the theft module shuts down operation of the vehicle, unfortunately the dealer is the only one that can turn it back on that is usually the case for these cadillacs.

what is the answer. I did not see it.

Sounds like a blown fuse

I have a trans pressure module circuit code on my caddy eldo , where is it located and how can I fix it myself?

The 1991 DeVilles have a replaceable motor, but you wont know what is needed until you get the door apart. Most of the time on the early models it was just the motor

start with fuel filter if you are able to hear fuelpumpworking when you turn key on.