Having problems with your 1998 Pontiac Grand Prix ?
Has a mis changed plugs and wire scan tool says mutiple cylinder mis fire
Most likely the fuel injectors need cleaning,try lucas fuel treatment.
Repair Help & Product Troubleshooting for 1998 Pontiac Grand Prix
Tips for a great answer:- Provide details, support with references or personal experience .
- If you need clarification, ask it in the comment box .
- It's 100% free, no registration required.