Where is the fuel filter on a 1998 oldsmobile 88LS6 cylinder

Answered in this link. Plus pictures on the Parts websites. Follow the fuel line from the tank. It is a small metal cylinder.

https://www.google.com/search?q=1993+oldsmobile+eighty-eight+royale+replace+fuel+filter

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It is under the car along the railing between the tank and the engine . According to this source.



http://www.autozone.com/autozone/parts/1998-Oldsmobile-Bravada-AWD/Fuel-Filter/_/N-jacltZ8vdbw
(copy and paste to view)

have you checked fuel pump relay?

Here's a link to your fuel filter,first remove fuel pressure. Component Locations Fuel Filter AutoZone com

he fuel filter is located along the driver side frame rail...

on the frame rail under the rear driver side door
be care when change the fuel line broke when I changed mine also the rear brake lines are right there

For the 1998 Oldsmobile Truck Silhouette 3.4L SFI 6cyl
The Fuel Filter is located under vehicle, center, below seating area, front of fuel tank, mounted on chassis.

Hope helped (remember rated this help) Good luck.

THE FUEL FILTER IS LOCATED UNDER THE REAR OF THE CAR NEAR THE FUEL TANK.

Top candidates for this problem are:
Clogged Fuel filter
Faulty Fuel pump
Clogged fuel injectors
Dirty / worn spark plugs

Of these, only the clogged fuel injectors are likely to respond to a gas tank additive, and even then you need to get the right kind of additive.
If your fuel filter has not been changed in a while (couple years), start with this. It is fairly easy to change. The fuel filter is under the car near the the driver's side rear door.
If this problem started "suddenly," then the fuel pump might be the culprit.
Fuel injector / spark plug issues are not likely to stop the engine right away, but would tend to cause it to miss cylinders, idle rough, or start rough.