Vehicle
Pontiac Grand Prix
The rear-drive-looking front-driver that carried the brand for a generation, and the supercharged 3.8 is what most people mean when they name it. That engine — the Series II and III L67 — is one of the best-documented in the American catalogue, and its two standing faults are the supercharger coupler and the plastic upper intake manifold at the EGR port, which melts and produces coolant loss with no external leak. The 5.3 V8 GXP is a different car entirely and shares almost none of that.
Generations
-
Fourth generation 1978–1987
The downsized rear-drive G-body car, carburetted throughout — the front-drive W-body that followed shares nothing with it.
- Body styles
- Coupé
- Platform
- GM G-body
- Engines
-
- 3.8 V6 — petrol
- 4.3 V6 diesel — diesel
- 5.0 V8 — petrol
- 4.3 — petrol · 6-cylinder, US market 1986-1987
- Transmissions
- 3-speed automatic · 4-speed automatic · 3-speed Turbo-Hydramatic
- Drivetrain
- Rear-wheel drive
-
Fifth and sixth generation 1988–1996
The W-body years with the 3.1 and 3.4 V6s; the 3.4 DOHC is a belt-driven engine and a different service proposition from the pushrod cars.
- Body styles
- Sedan · Coupé
- Platform
- GM W-body
- Engines
-
- 2.3 four-cylinder — LD2 · petrol · Quad 4
- 3.1 V6 — L82 · petrol · 251 Nm (185 lb-ft)
- 3.4 V6 DOHC — LQ1 · petrol · 157 kW (211 hp)
- 3.8 V6 — petrol · Series II
- 2.8 V6 — petrol · 97 kW (130 hp) · 230 Nm (170 lb-ft)
- Transmissions
- 5-speed manual · 4-speed automatic · 3-speed automatic
- Drivetrain
- Front-wheel drive
-
Seventh generation 1997–2003
The supercharged 3.8 era on GM's W platform — the upper intake manifold at the EGR port is the fault to rule out before believing a coolant or misfire code.
- Body styles
- Sedan · Coupé
- Platform
- GM W
- Engines
-
- 3.1 V6 — petrol
- 3.8 V6 — petrol
- 3.8 supercharged V6 — petrol · GTP, L67
- Transmissions
- 4-speed 4T60-E automatic · 4-speed 4T65-E automatic · 4-speed 4T65E-HD automatic
- Drivetrain
- Front-wheel drive
-
Eighth generation 2004–2008
Same platform, and the only Grand Prix with a V8 — the GXP's 5.3 is a different diagnostic proposition from every other car wearing the name.
- Body styles
- Sedan
- Platform
- GM W
- Engines
-
- 3.8 V6 — petrol
- 3.8 supercharged V6 — petrol · GT and GTP
- 5.3 V8 — LS4 · petrol · 226 kW (303 hp) · 438 Nm (323 lb-ft) · GXP
- Transmissions
- 4-speed automatic
- Drivetrain
- Front-wheel drive
Information, not instruction
CarGeek is a reference, not a service manual. Its pages are written from public sources and from what other people have found, never from a manufacturer's own service information, so they can be wrong or incomplete for your particular vehicle. Some of what they describe carries real risk: high voltage, fuel under pressure, stored energy, hot and moving parts.
Have anything you intend to act on checked by a trained person against the manufacturer's own procedure for your vehicle. Nothing here replaces that procedure.
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