Engine Mechanical
WARNING: This page is about a different car, the 2003 Pontiac Grand Am, 2003 Oldsmobile Alero, 2003 Chevrolet Monte Carlo, and 2003 Chevrolet Impala. However, it is still accessible from the selected car via links, so may be relevant.
- Excessive oil in combustion chamber or leaking valve seals.
- Low cylinder compression. See COMPRESSION under MECHANICAL INSPECTION under PRELIMINARY INSPECTION & ADJUSTMENTS in BASIC DIAGNOSTIC PROCEDURES - 3.4L ALERO, GRAND AM, IMPALA & MONTE CARLO article.
- Improper valve timing.
- Combustion chambers for excessive carbon buildup. Clean the chambers using top engine cleaner. Follow manufacturers instructions on the can.
- Check for incorrect basic engine parts. Check the camshaft, cylinder heads, pistons, etc. Go to appropriate article in ENGINES.