According to one of the Ford websites :
For a 1988 Mercury Cougar , 3.8 liter V6 engine :
( the spark plugs are gapped at .054 inch )
According to one of Fords websites : For the 3.8 liter V6 engine in a 1988 Mercury Cougar : ( the spark plugs are gapped at .054 inch )
.054 inch ( according to motorcraft . com )
1988 cougar will not crank over
The 1988 Mercury Cougar diagnostic port can be found under the hood.
inside of the tank
driver side footwell under dash.
http://www.coolcats.net/tech/troubleshooting/heatercore.html
For a 1988 Mercury Cougar : According to my Chilton's Auto Repair Manual : For the 2.3 litre turbo ( 18 U.S. gallons ) For the 3.8 litre V6 ( 21 U.S. gallons ) For the 5.0 litre V8 ( 20.7 U.S. gallons )
You failed to list if it is a V6 or V8. Click the link and then choose the correct engine.
The 1988 model, 20 hp Mercury requires a NGK BP8H-N-10 plug gapped to .040 in.
I set mine at .035
top of engine bay 2ft or longer extension 13mm swivel socket