judd944

After my DE at Putnam I drove about 45 min before stopping for fuel. the last gas station was a junky Marathon station against my better judgement I filled up here.
20 min later on the interstate I had the cruise on and as I was going up a slight incline my CE light flashed 4-5 times then went off. It did it again about 10 min later. Still not staying on and it only flashed a few times.
I called my tech and on his advice pulled over and read the coded.
P0300
P0301
P0302
P0303
P0304
P0305
P0306

Misfires on 1-6. he thought I had bad fuel. I drove it like that for another 100 miles and slowed my speed to 70. I would only feel the misfires on the steep inclines where the engine was loaded.

After I ran it down to 1/4 a tank I stopped at a Shell station and put in 8 gallons hoping to dilute the bad fuel. No dice, still doing the problem. I only showed misfires on 1-3 this time.

Think I fouled my spark plugs?

I pulled my car over the pit and I will check underneath tonight to make sure nothing is loose. I went off track twice but both times I drove straight off at only ~20mph. plus I drove ~50 miles after my last "off" without any issues.

Dock

When did you last change your plugs?

judd944

24k. The PO had them changed
I am at 42k now. I bought the car at 29k 1.5 years ago. It could be time for that.

Dock

Regarding the Marathon gas; I believe all stations in a local area get the same basic gasoline, with the only difference being the additives each brand may or may not add to the fuel. It may be that your plugs were close to needing changing before the Marathon gas, and with potentially less cleaners in that gas, it was enough to push your plugs to misfires.

Just a guess.

Dock

Additives:

Premium Unleaded 92 or 93 Octane (per 100mL)

Shell 31.0mg
BP 26.4mg
Exxon 21.2mg
Speedway 10.6mg
Mobil 10.6mg
Citgo 9.4mg
Marathon 9.0mg
Pilot 8.8mg

Article:

http://www.wxyz.com/dpp/news/region/...is-in-there%3F

judd944

Thanks Dock. I did not get any fuel within 30 miles of that station so I am unsure of what the local fuel is like. That article tells me I am doing right by using Shell !

With all the labor to change the plugs I might just change the coils as a preemptive strike to the 60k service.

Kevin

Plugs, Coilpacks and wideband O2 (your at the 50K mark)..

996TWINS

How often should you change the plugs with a tune, street driving only, and track and street driving?

Dock

I have EVOMS Stage 2 tuning and have over 24k miles on my current plugs; they're still running strong.

996TWINS

Same here, still running strong. I have 25K with an EPL Stage 1 tune.

I guess the 30K service interval still applies.

NYC996x50

I had slight misfiring at 42k miles, no CEL. Had plugs and coils changed. Problem fixed. Had the MAF cleaned recently... runs much smoother!

judd944

Going to be an expensive month for the Turbo ! new tires, Plugs, coils, and a wideband O2 sensor.

I will not have time to DIY this until next month so I may order the parts and let it sit for a few weeks.

NYC996x50

I hear ya. I did plugs, coils, clutch, and flywheel in one month last year.

Danyol

I was getting hesitation; Plugs & Coils replaced and the problem is gone. I had replaced them only 20k before torqued to factory specs, they were all loose. Perhaps yours have loosened up?

Good job to do oneself, save a lot of labor $

BTW I purchased Kevin's high speed logger device, he compared my log from last year and could see issues.

jimq

I just got a code the other day for misfire on 6 (3006) while the car was ideling in my garage. Cel came on I shut it off and hasnt come back on in 50 miles or so. I read on here it could be a cloged injector so dumped in some techron. Can i change the coilpack on 6 without taking off the bumper. Also which one is #6? Plugs only have 12K on them.