By
shawn99corolla, September 9, 2014
Still getting P0303 (cylinder #3 misfire) code after: New spark plugs, new spark plug wiring, new coils, new injectors, full tune up. 99 Corolla 147,000 miles Any ideas?
what else could it be? o2 senor? or maybe intake manifold leak? valve leak? what am I missing? Any suggestions appreciated.
Leaking intake manifold a possibility, not as common on the 8th gens compared to the composite intake on the 9th gen Corollas, but still can happen. Could also be internal - excessive deposits in that cylinder, burned valve, etc.
Compression tested the engine recently?
