Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
Model Identification
Reference will be made to body style codes for GM cars in the vacuum diagrams index. Refer to the table below for identification of these body style codes.
| Body Code | GM Division | Model Name |
|---|---|---|
| A | Buick | Century |
| A | Chevrolet | Celebrity |
| A | Oldsmobile | Cutlass Ciera |
| A | Pontiac | 6000 |
| B | Buick | Estate Wagon, LeSabre |
| B | Chevrolet | Caprice Classic, Impala |
| B | Oldsmobile | 88 |
| C | Buick | Electra |
| C | Cadillac | DeVille, Fleetwood |
| C | Oldsmobile | Ninety-Eight |
| D | Cadillac | Fleetwood Limousine |
| E | Buick | Riviera |
| E | Cadillac | Eldorado |
| E | Oldsmobile | Toronado |
| F | Chevrolet | Camaro |
| F | Pontiac | Firebird |
| G | Buick | Regal |
| G | Chevrolet | Malibu, Monte Carlo |
| G | Oldsmobile | Cutlass |
| G | Pontiac | Bonneville, Grand Prix |
| J | Buick | Skyhawk |
| J | Cadillac | Cimarron |
| J | Chevrolet | Cavalier |
| J | Oldsmobile | Firenza |
| J | Pontiac | J2000 |
| K | Cadillac | Seville |
| T | Chevrolet | Chevette |
| T | Pontiac | T1000 |
| X | Buick | Skylark |
| X | Chevrolet | Citation |
| X | Oldsmobile | Omega |
| X | Pontiac | Phoenix |
| Y | Chevrolet | Corvette |
| Engine & Make | Body Style | Application | Trans. | Fuel System | Fig. No. |
|---|---|---|---|---|---|
| 1.6L (98") 4 Cyl. (VIN C) Chev., Pont. | T | Federal | Both | 2-Bbl. | 1 |
| 1.6L (98") 4 Cyl. (VIN C) Chev., Pont. | T | Calif. | Both | 2-Bbl. | 2 |
| 1.8L (112") 4 Cyl. (VIN G) Buick, Cad., Chev., Olds., Pont. | J | Federal | Both | 2-Bbl. | 3 |
| 1.8L (112") 4 Cyl. (VIN 0) Buick, Pont. | J | Federal | Both | EFI | 4 |
| 2.0L (122") 4 Cyl. Cad. | J | Hi. Alt. | Auto. | 2-Bbl. | 5 |
| 2.5L (151") 4 Cyl. (VIN R) Buick, Olds., Pont. | A, X | Hi. Alt. | Both | EFI | 6 |
| 2.5L (151") 4 Cyl. (VIN 2) Pont. | F | Hi. Alt. | Both | 2-Bbl. | 7 |
| 2.8L (173") V6 (VIN X) Buick, Chev., Olds., Pont. | A, X | Federal, Calif. | Both | 2-Bbl. | 8 |
| 2.8L (173") V6 (VIN X) Buick, Chev., Olds., Pont. | A, X | Federal, Calif. | Man. | 2-Bbl. | 9 |
| 2.8L (173") V6 (VIN Z) Buick, Chev., Olds., Pont. | A, X | Calif. | Auto. | 2-Bbl. | 10 |
| 3.8L (229") V6 Chev. | G | Federal | Auto. | 2-Bbl. | 11 |
| 4.1L (250") V8 (VIN 8) Cad. | C, E, K | All | Auto. | DFI | 12 |
| 4.3L (262") V6 Diesel (VIN V) Chev. | G | Federal | Auto. | Fl | 13 |
| 4.3L (260") V8 (VIN 8) Olds. | B, G | Federal | Auto. | 2-Bbl. | 14 |
| 4.4L (267") V8 (VIN J) Chev. | B, G | Federal | Auto. | 2-Bbl. | 15 |
| 5.0L (305") V8 (VIN H) Chev., Pont. | B, F, G | Federal, Calif. | Auto. | 4-Bbl. | 16 |
| 5.0L (305") V8 (VIN H) Chev., Pont. | F | Federal | Man. | 4-Bbl. | 17 |
| 5.0L (307") V8 (VIN Y) Buick, Olds. | B, C, E | Calif. | Auto. | 4-Bbl. | 18 |
| 5.7L (350") V8 Diesel (VIN N) Buick, Cad., Chev., Olds., Pont. | B, C, E, G | Federal | Auto. | FI | 19 |
| 5.7L (350") V8 Diesel (VIN N) Buick, Chev., Olds. | B | Hi. Alt. | Auto. | FI | 20 |
Use the Manual With the Right Hardware
Pair factory procedures with proven DIY tools so the instructions are easier to execute.
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.
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