05F150XLT

Last night I was merging in my 2005 F150 5.4 on to the interstate and my CEL was flashing, and I had a loss of power, this went on for about 45 seconds, the light went from flashing, to steady on. this morning I went to Advanced auto parts to have my codes read, and it came up p0308 misfire on cylinder 8, I continued to drive today, and the misfire doesn't seem existent anymore. I was wondering if it was possible that it went away, or if this could be an intermentit problem. My other question is should I just go ahead and replace my ignition coil and spark plug?

(Advanced won't erase the code so I am taking somewhere tomorrow to have it erased.)

Thanks in advance for your help.

rickyp

I doubt that the pablum repaired it's self.

Once you have the code erased it will come back unless the problem is resolved before it is reset.

05F150XLT

well i didn't think that it fixed itself. I just didn't know if this could be an intermittent problem, and if it was would the CEL turn off?

Lenn

I am no grammar major and I hate to sound like a rectum (after all, we've all seen much much worse on here) but I really think that is spelled wrong.

rickyp

the spell check got me again, I didn't watch what it suggested and clicked change

Lenn

I'm just giving you a hard time, man.

rickyp

no worries. I fully admit that I suck at spelling. I am a product of public education

primalurges

you've got a bad coil on #8. The CEL only goes on permanent after it has detected the misfire on three warm up cycles. If you reset, it will come back after the misfire is detected a few more times. misfires can damage your CATs and they are a lot more expensive than a $25 coil. you should change it however, skip the plug change as it is unlikely the cause of the problem and can turn into a headache if you screw up the change.

05F150XLT

I changed the coil today and reset the computer and drove for about 17 miles to see if the code would trip again, but it hasn't. I haven't changed the plug yet. It still had a shudder when I gave it about 3/4 throttle while i was on the interstate. Like you said it can damage my cats, and I don't want the problem to get any worse, and I'm about to make a 700 mile trip to top it all off.

Mr.Bones

i would pull that plug and replace it, have you driven in any heavy rain the past few days?