PONTIAC GRAND PRIX ENGINE POOR MILEAGE

I Have A 1999 Grand Prix 3.8 That Is Not Supercharged. Im Getting 13 Mpg With It And I Know It Should Be Much Higher Than That. The Car Runs...

I Have Experienced A Significant Loss Of Fuel Economy. Egr Valve Is Good, Mass Air Flow Is Good, No Fuel Leaks, Fuel Pressure Regulator...

2001 Pontiac Grand Prix 6 Cyl Front Wheel Drive Automatic 114 Km Miles My Grand Prix Sat For Two And A Half Years. I Changed All Plugs...

After Changing And Overfilling My Crankcase By A Quart Of Oil And Taking A 450 Mile Trip With It Overfilled. I Started Having Poor Mileage...

My Car Is Using Hundred Miles Per Tank Less Than I Was Getting A Few Has No Kickdown Power Will Not Get Up And Go Other Than That Runs Fine...

My Car Gets The Gas Mileage It Should From Full To About 3/4ths A Tank From 3/4ths To Half I Get Maybe 20 Miles And Then From Half To A...

I Have A Question Regarding Our `02 Grand Prix. Normally We Get Around 25-34mpg Or 400-425 Miles On A Tank Of Gas And Recently We Have...

Hi. My 2001 Grand Prix Has 230,000 Miles On It And Still Runs Well. Lately I Have Noticed That My In-town Gas Mileage Has Been Awful. If I...

I Have A 2004 Pontiac Grand Prix With 40,000 Miles. The Emmission Light Came On And Is Staying On Solid. I Read The Owners Manual And...

I Have Seen Some Of These Performance Chips That Are Claimed To Boost Torque And Mpg, Do Any Of These Actually Work Or Worth It? I Have...