code p0304 ford f150
 

cleaned and re oiled my k n air filter. now it runs rough and engine light on. code says p0304. which is saying cylinder 4. i cleaned my map sensor and bought new air filter just in case too much oil from air filter, but same thing question is should i buy a new $100 map sensor and see if works. or should i take it in to have someone take out #4 plug and look at it.

Likely a misfire on your number 4 injector. Could be many things that cause that. Let it ride and see if it clears. If not, seek assistance

On my computer, That code came up as "Buy a Dodge"

think Advance Auto has a code reader

autozone read it for the code. how long to drive it to see if clears up. and would driving it mess something else up.

Don't touch the map sensor. All it reads is load. Fords have a single coil over each spark plug and they are notorious for going out......it prolly wont clear up, but you can pull the plug, clean it, clear the code and see what happens

what yr truck? I had a 97 and 01 and both had problems with coils

2003 f150 5.4. read from others if i had excess oil on filter it could have contaminated map sensor. which would could have sent wrong mixture to plugs which is what fouled it up. how hard is it to remove plug in the 4 slot on this ford.

Disconnect battery terminals for at least 5 mins. & see if it clears. Also check that plug wire & make sure it's nit touching metal or another plug wire, they will jump fire, sometimes you can crank engine after dark with no lights & see fire jumping, sounds like there's a misfire, could be a plug wire or that coil.

Mine too


---
- Sent from my iPhone using Tapatalk

maybe you should drop a dodge on that boat

went and disconnected. i'll go check in a little bit. sounds like a good idea though to reset the system. i've been told it was difficult to get to the back spark plug. what ya think. it looks awkward for sure

Ford did a tune up on my 05 and by the time they got the back plugs out they had the cab off:eek:, how adventures are you

What I think is the SOB's that build this should have to work on it!!!!! I hate engineers!!!!!

connected battery back. check engine light went off , took for a 3 mile spin and still riding rough. i did also spray some carb /choke cleaner in the intake. wonder if some loosened up junk sucked in would make it run like this????

does it run any diff when it ideals then when you are driveing?If I remember right mine would ideal pretty close to normal but when you gave it gas it was like it had a miss

if in neutral its idles perfect. at the red light in gear it wants to struggle. floor it and it goes pretty close to normal . its when let off gas it gets rough

sounds like coil, I had a problem also with the cat. pluging but it would ideal ok but struggle when you gave it gas in gear

replace #4 coil,they are about $60,just one bolt & a plug,this is a commonproblem on fords.

Just had #4 ignition coil replaced on an '04 ford last week. $65 and took about an hour.( they had to find the right tools) works fine now, it would "miss" when in OD and when I would give it a little gas

now its working. i placed the coil on number 4. took 5 minutes to get off and 15 to put on. would of taken less to put on but didn't know or couldnt tell if far enough in. any way started it up and took for a spin and everything seems fine. cost me $40. thanks for talking

Glad to hear you got it going.

I hate ford's old COP 2-pc design & the one before that spit plugs from the block. hopefully they got the 5.0 right

I have an 01 with same motor and 4x4.I have a 3 in lift so getting to them is pretty easy.#3 went out first,it blew the plug out and detroyed the coil,that cost 1300 for them to pull the head and fix it,its been one coil after another since then.Its easier to just change all 8 at the same time b/c they are going to go out!I would also suggest you get a summit catalog and buy the hotter burning performance coils and they are actually cheaper!