I have a 2003 ford f150 with 322,000 miles. She's been my baby. Yesterday I drove to an interview and three different times when I got to a stop sign it died. I started back up immediately and drove. A couple of times a week ago the cel started blinking going down the road and it started missing bad. I pulled over and it started running fine again. The cel codes that pulled up was po171 and po 304. Any information will be greatly appreciated.

 

You have a cylinder misfire #4

 

I am dummy lol. What do I do to correct it?

 

Have you ever had the plugs or COP's replaced?

 

I had all of the plugs replaced a while back less than 30000 miles ago and changed two coil packs. If it was a coil pack or plug would it do it intermittently and would it be constant?

 

Yes it can. Swap the COP to another cylinder and see if the code changes to that cylinder.

From my experience those cops can last any where from 20 to 120k miles.

 

This may be a dumb question but which cylinder is the number four?

 

Passanger side very back plug

 

Lol the fun one to get to