P0301 Code-misfire
 

What's up guys!..

Ok, so i'm working on my friends 2.5 liter 1999 Ranger, about 3 months ago I replaced the fuel pump and has been working flawlessly, now he calls me up saying there's really rough idle and shaking when driving and hes Engine light is on... I have a code reader and came back as p0301-misfire cylinder 1.

I bought and replaced all (8) spark plugs and wires, NOT the coil packs though. When I took out cylinder 1 spark plugs, I could see and smell fuel on them,the other plugs where normal.

What does the fuel on the spark plug tell you? I'm guessing its a faulty injector that's just stuck open?..not sure.

Also after replacing plugs and wires with no change in roughness, I pulled the wires off the coil packs to just see if there were sparks..cylinders 2,3,4 all had spark coming from coil pack to wire, but cylinder 1 had no spark..on both coil packs. So what is going on here? I switch the coil packs around to see if that makes a difference, nothing.

Why is there spark from the coil pack to plug wires to cylinders 234, but non from 1? Any help would be greatly appreciated..

Sounds like ur ignition control module, take it off to get it tested at autozone or oreilys. My stang was doin the same, also swapped the coils but nothin, then got the icm tested and replaced. Their like $120 new or like $40 at junkyards

GO GO POWER RANGER!!!

Re: P0301 Code-misfire
 

his ICM is part of the pcm. it's possible you have a bad pcm....not sure I would look around at the connections.

Ur right it doesnt have icm, my bad!

GO GO POWER RANGER!!!

Re: P0301 Code-misfire
 

Can you get the PCM tested?

Re: P0301 Code-misfire
 

a misfire in my supercharged cavalier was driving me nuts, cylinder #2. I checked my vacuum system, fuel system, plugs, ignition module, everything.

turned out i had loose intake manifold bolts and there was an undetectable leak. more than one bolt was loose. make sure all his manifold bolts are nice and tight. might even take them out, use some locktite and put them back in. may not be your issue but its always something simple when you find out what it is that makes you smack ur head lol..