Many waste spark and coil over plug systems require a cylinder identification signal so that the ignition coils can fire in the proper order during start up. If the computer does not receive a cam sensor signal, some engines may not start. Some may take a few attempts while the ignition module or PCM guesses at coil sequencing. The PCM will attempt to synchronize and look for an increase in the mass airflow sensor (MAF) signal. An increase in the MAF signal will indicate that the engine has started. If the PCM does not detect an increase in the MAF signal, a re-sync will occur to the opposite cam position. If the engine fails to start on the first attempt, try turning the key off and then try again. If the engine starts normally on a subsequent attempt, look for a problem in the camshaft sensor circuit. Some systems use the camshaft sensor only for control of sequential fuel injection.
Faulty or fouled spark plugs along with a faulty ignition control system due to loose connections, bad grounds, high resistance in the circuit, or opens in the circuit can cause the following symptoms: