Engine Mechanical
WARNING: This page does not describe the selected car, but rather 7 other vehicles, including the 2003 Pontiac Grand Prix, 2003 Pontiac Bonneville, 2003 Chevrolet Monte Carlo, 2003 Chevrolet Impala, and 2003 Buick Regal. However, it is still accessible from the selected car via links, so may be relevant.
- Check for excessive oil in combustion chamber. Check for leaking valve seals. See appropriate article in ENGINES.
- Check for low cylinder compression. See COMPRESSION under MECHANICAL INSPECTION under PRELIMINARY INSPECTION & ADJUSTMENTS in BASIC DIAGNOSTIC PROCEDURES - 3.8L BONNEVILLE, GRAND PRIX, IMPALA, LESABRE, MONTE CARLO, PARK AVENUE & REGAL article.
- Combustion chambers for excessive carbon buildup. Clean using top engine cleaner. Follow manufacturer's instructions on can.
- Inspect for incorrect basic engine parts, such as camshaft, cylinder heads, pistons, etc. See appropriate article in ENGINES.