1997
- Master cylinder/fluid reservoir setup is different than on newer years
- Unique PCM for this year only had a removable chip making case learn unneeded
- Larger windshield washer fluid reservoir on top of battery
- Alternator and mount is different than the newer years
- Coolant temperature display starts at 100
- The 97s DO NOT have tire pressure sensors. The 97s have the Delco Delphi ABS system, which could not handle the GTP power for TCS. So TCS was disabled on the 97 GTP, but works on the GT and SE. The "Tire Pressure" light was part of the Delphi ABS system; it did not sense pressure but noticed differences in tire rotation speed. When the Delphi was replace with Bosch, TCS was enabled but the "tire pressure" light was lost.
- Some of the 97s had a prop rod instead of struts to hold up the hood. Some had under hood lights, too.
- Rear fender mast antennas were common for 97s because they ran out of rear window antennas at the factory. Those with mast antennas were credited $15 on the sticker.
- Transmission input shaft is a little stronger from a better O-ring groove radius
- Complex EVAP system that uses an extra part not found on newer GPs
- M90 has an extra vacuum port
1998
- Fixed fuel level sending unit problem
- Larger gas tank
- New PCM used through current models with some minor changes each year
- Coolant temperature display now starts at 160
- New shrouding and mounts on the fans to make them more efficient
- Moved the windshield washer reservoir into the passenger fender
- Performance shift indicator light added to gauge cluster
- Last year of GTP being an option for a GT
- Daytona Package available (Medium Blue Pace Car Daytona Edition with torque star rims)
- Went to Dual digital climate control
- 98+ the gas cap is tethered to the fill tube
1999
- Fixed the headlight condensation problem
- Better air box draws air from behind headlight and uses larger filter
- Moved coolant tank reservoir to side of strut tower
- MAF sensor is setup different
- Torque star rims available
- Fixed fuel pump resistor problem
- Fixed malfunctioning wiper problem
- Digital climate control now illuminates in red
- Bose sound system was added in 1999 as an option for the first time.
2000
- Added a small reservoir to the fuel line on top of the SC
- More plastic shrouding in front of the radiator
- Added the child seat anchors on the package shelf
- Went from Passkey 2 to Passkey 3
- In 2000 the dual digital climate control's previous "AC" button has been renamed "ECON" and the LED indicator works opposite, lighting up when the A/C is cancelled, rather than lighting up when it's working
2001
- The injectors and injector wire plugs were changed on the L36
- Different sun roof cover doesn’t split in the middle making it look like two pieces. It looks like one solid piece. There are vents in the cover near the handle. These vents allow you to position the sunroof just so it lifts up in the back, and keep the cover closed.
- DRL and Auto Headlight electronics more complicated, making it harder to disable
- On-Star cell phone antenna on rear window
- Removed performance shift
- Removed digital climate control
- Replaced the lights in the doors with reflectors
- New steering wheel with a smaller center
- The 2001 cars have an inch deeper cup holder
- Special Edition available
- New bracket on rear of coil pack mount
- Plastic gas tank
2002
- 40th Anniversary Edition available
Other
- The 1997 has 3 bolts that hold the hinge to the body of the car where as the 2001 only has 2. On the 1997 one of those bolt holes in the hinge itself are slotted so to remove the hinge from the car you don't have to fully remove that bolt. The other two you do. The 1997 hinge has rubber bumper stops in its down resting position and in its open raised position. On the 2001 it doesn't have ANY rubber bumper stops what so ever. It does have a bolt adjusting screw for the "down position" so the hinge doesn't go too far down and do damage to the body of the car.
- Side mirrors on the 98+ and some retrofitted 97s have a little lip underneath to reduce wind noise
- BOSE systems in 99+ caused radio problems with aftermarket systems
- On-Star in the 01+ caused radio problems with aftermarket systems
- It is generally agreed that the 2000 was the best year for the 97-03 body style
- 1998 is said to have had the best Throttle Body
-1997 is said to have a generally stronger transmission, not just an input shaft
- In 2003, a lot of subtle changes were made to the Grand Prix, possibly to help with the 2004, but these changes are enough to complicate some aftermarket applications
- In 1997-1998’s a 99 style coolant bottle is required for the use of an aftermarket cold air intake.
