About a week ago while driving to work my engine sputtered a bit and the CEL came on and then went off. As I drove the sputtering reoccured when I would excelerate from being stopped but went away when I got to higher speeds. Again the CEL came on. Next day I took it to the dealership who read a P306 code and was told it was an issue with the No. 6 cylinder. After driving a few more miles the sputtering stoped happening. The next day I got in, started the van and no more CEL. That was last Wed, and since then I have done over 150 miles of driving and no sputtering and the CEL has not come back on. Could I have just gotten some bad gas or something that caused the brief sputtering and CEL.
It is possible, but not that likely, IMHO.
“Bad gas”–which is actually less common than most people think–would cause problems in all cylinders, not just #6.
Please refresh my memory regarding the vehicle’s maintenance.
When were the spark plugs last replaced?
No clue on the plugs. I have done a number of things on the van since purchase in Aug of 2010, however a replacement of plugs/wires has not been done as van was running well and figured the other items I got done:
Replaced trans fluid
Replaced all belts
Replaced Starter (had to)
Replaced crank shaft sensor (had to)
Had allignment done
Removed/replaced cooling lines to back heater
Multiple Oil changes
Replaced air filter
So up on my to have done list is new plugs, change out brake fluid and anti freeze, replace back shocks and front brakes in the coming months. Van had 135,000 miles on it when purchased, and have put 12,000 on it since then.
When spark plugs are allowed to remain in place for an extended period of time, in addition to performance problems, starting problems, emissions problems, and reduced mpg, there is also the very real possibility of the plugs being “frozen” in place, and taking fragments of the threads with them when they are removed from the cylinder head. That is why I advised (a week or so ago) that, unless you knew for sure that they had been replaced on schedule at 90k miles, it is very important to replace them a.s.a.p.
I would suggest putting the rear shocks on hold for the time being, and bumping the spark plugs to the top of your list, along with the brakes and the brake fluid.
I hope that those spark plugs come out without damaging the cylinder heads!
Well, the code is a misfire code for cylinder 6, and at 147,000 miles it’s likely overdue for its second set of replacement plugs. Typically 60,000 to 70,000 is reasonable life for even irridium plugs, although I’m aware that some claim they can be run for 100,000 miles.
“Read” the plugs when you pull 'em just for the heck of it. I’m sure there’s nothing in my reply that you’re not already aware of. I’d be curious as to the condition of the plugs.
“Bad Gas” would produce a “random misfire” code, not one limited to the #6 cylinder…If access to the spark plugs is limited, chances are they have never been changed…I would pull the easiest one to get to and see what it looks like…
Zero chance of me pulling anything, I leave all car work to the professionals, I struggle just to put gas in. I had the dealer run a full diagnostic check and they felt at the time (this was done when I got the van) that the plugs and wires looked okay, but I will just look into replacing them all.
Why are you taking it to a dealer? Most of the time all you get there is more “selling,” more expensive labor, and more expensive parts. You can normally do much better on both service & price with a good, local, independent mechanic (read: NOT corporate “auto care” chains).
I have a great dealership here. Price wise they are equal to everyone else. When it came to changing out timing belt very few places near me wanted anything to do with it and wanted at least $200 more to do it. Also Kia requires special fluids and some parts that cost more and you can’t use just basic stuff. Example is transmission fluid, if you don’t use the Kia brand you can screw up the transmission. To change out the fluid they charged me $70. To do the timing belt and other belts and crank shaft sensor it was $525. Only did I have the starter done somewhere else