It is a mechanical fuel pump located on the engine.
It is in the drivers side front below the distributor.
20.3 gallons
Driver side
If it has a 360 motor the mechanical fuel pump is located below the distributor. there could be an after market electrical fuel pump located near the tank. these answers are based upon my 89 grand wagoneer with a 360. The fuel pump on an 88 Wagoneer is in the fuel tank itself.
if it has the 360 engine look on below and behind the distributor. you can follow the fuel line from the carb to it.
A few possibilities here. Oil and oil filter issues, fuel injector issues, cam issues.
The fuel pump is located in the the top of your fuel tank.
twenty gallons
Its a manual / mechanical fuel pump. To check it remove it a look inside. It will be obviouse if its bad. More importantly if its running its not bad. There are no injectors on a 87 Grand Wagoneer. Its corroborated.
Electric.
20 gal
the fuel capacity for jeep grand wagoneer in the 80s is between 22 gallons and 25 gallons depending on the engine size
check for: Spark Fuel Compresssion