About a month ago I replaced spark plugs and wires (8mm Magnecores)and had the valley pan gasket replaced. Two days ago, I got the SES light. The fault code was P306. The work is under warranty, but my shop is currently closed to relocate. The fault code is active (flashing light) when I leave for work in the morning and flashes for 10-15 seconds. I've read that this could be a possible vaccum leak...is that the most likely scenario? Any other ideas?

Thanks for the help. By the way, it's an 04 with 55k.

 

Update:

So, this morning on my way into work (it was about 40 degrees outside and my commute is 6 miles), I got the flashing SES light when accelerating up hills and on my merge onto the highway. I'm going to re-read the code this evening. Assuming that it is still P306, bad spark plug (although only one month old)? There is no loss of coolant, no smell of coolant in exhaust, and the idle seems to be smooth.

 

In case you haven't read your owners manual, it is not advised to drive with a flashing check engine light on. You have a mis-fire, not a vacuum leak, so inspect the plug to see if it is cracked, make sure the #6 wire is secure on the plug and coil pack.

 

Mike, thanks for the response. Since I've noticed the flashing--I'm doing my best to limit driving the vehicle as I don't want to risk additional problems. I'm a bit hamstrung right now by the relocation of my mechanic. I'll climb under tonight and see if I can check the connection and possibly pull the plug. I don't have a garage or driveway, so I'll have to do my best on the street...