This is likely that this is an after market installation. You should start by checking the power and the grounding.
what is the firing order for a 1987 mercury cougar v8
You can find the correct firing order for your 1987 mercury cougar at www.coolcats.com, it is a website dedicated to the cougar and thunderbird.
CID?
They Call Me Mr. Trunk was created on 1987-12-17.
yes
If I remember right, it's in the glove compartment, on the left side beside the power trunk release.
I have a 1987 Mercedes that has no trunk key. Do I remove the back seat to get in?
a fuse, relay, bad ground or positive wire at switch or solenoid, etc.
According to a website I was looking at : For a 1987 Mercury Cougar , 3.8 liter V6 , 4 speed automatic transmission ( 17 city / 24 highway , miles per U.S. gallon )
1987
I still have my 1987 XR7 sticker. It listed for $17,200. Bought 12-15-1996. Still a great car!
about 300 at the block about 220 at the wheels