Pontiac Repair: 2007 Pontiac Torrent V6- Check Engine Light On, spark plug wires, cylinder misfire

Question
The check engine light came on in the car over the weekend.  The car will shake (hesitate, shudder) and the light will blink and the tachometer will drop while this is going on.  When it isn't shaking the check engine light stays on steady. I checked the gas cap and it is on tight. Thank you for any suggestions.

Answer
Hi Susan:

The torrent is misfiring and under a load it's doing it more so then at a cruising speed. Does it do it worse in the am when it's damp or when it raining out? If so it's more then likley aan ignition system issue either a cracked spark plug or leaking spark plug wires. If the humidity leve have no effect on it it could be a fule delivery issue like a plugged/restricted fuel injector. with out knowing what code(S) are stored it's hard to say for sure what's wrong. It may just have a code p0300 which is a genaric random cylinder misfire. It's going to have to be hooked up on a scan took and see which cylinder(s) are misfiring and go from there. if this is less then 3 years old and less then 36,000 miles on it the repair should be covered under warranty. Good luck :)