ran codes on my "03 supercrew
 

I ran the codes came up with Po301 #1 misfiring....*L* I don't think it can be any more veg...last time which was last week it did this and I put in some gas dry and it cleared up...not this time..?????any ideas

Plug or COP

replace COP #1

10 MINUTE JOB

Put a new plug in there too.

Steve

Disconnect the neg cable first :D

cop?.....

just went out and started truck runs perfect this was after adding a 2nd can of dry gas and sitting over night, but what has me puzzled is it has rained hard both times this has happened.?????? the gas bought was bought in 2 different states but were back to back fill ups

C.O.P. - (coil on/over plug)


PLUG - Sparkplug - inDhead~CopDcover.

Thought we covered that.

We just told you how to fix , cause , you asked.


You have a "Coil On Plug" system in the 03 . It's common for a plug or coil to go bad every now and again..That's what were getting at . Misfiring for long periods of time is bad for the cats. PO301's Injector is probably good, but dumping raw fuel down #1. You need to fix it.

You have the code #1 's first one pass. side (towards the front of the truck.).. After time goes by , your PCM may shut down your injectors in an effort to protect your CAT's - so, yeah , try a plug and a COP from Auto-Zone.

COP's
https://www.f150online.com/galleries...940-176816.jpg
PLUGS
https://www.f150online.com/galleries...943-170388.jpg
Heres a pic of #1 - The one you need to fix -
https://www.f150online.com/galleries...939-155580.jpg
A pic of injector #1 - down by the oil filler cap - that orange thing sprouting from the fuel rail and blowing un-burned fuel thru #1 . The COP and Plug are behind that out of view.
https://www.f150online.com/galleries...939-174553.jpg

See what we are gettin at?

I'm here laughing my ass off..I'm no noob to engines..I build them for a living.(race engines).just didn't know the cop thing. I do thank you for the help though

well it started it again..coarse it rained last night..install new plug old one looked good still missing pulled cop off with truck running it was firing..put it back on them I pulled the injector harness off #1 there was no change same miss didn't get any worse.. you guys still think c o p ?

Sounds like the injector lol.. Common race car man...:devil:

A lot of the time it's the boot that's bad. The spark jumps to the head instead of through to the plug gap. You can't rule out the COP just because it's sparking when you pull it out. Or the COP's output is too low. We see that a lot. It fires fine, but it still misses because the fire's not strong enough to light the charge. Plus, it's about 100x more likely that it's either the boot or COP than the injector.

I betcha if you move the cop to the next piston it'll show that one's missing.

He said there was no change unplugging the injector. ???? Significant change when unplugging COP. AND , it's missing at idle..I realize COPs miss under certain load values, this ones misfiring at idle , it has no fuel to ignite or very little..Therefor primary and secondary are good. His injector F'ed..