How To: Change a C.O.P.

Not to sound stupid but how can you tell if you have a misfire? I'm at 115k miles on factory plugs.. i don't know what to feel for

 

It'll feel like someone is sitting in the seat behind you shaking your headrest, an sound like someone is kicking a floorboard. I'm serious

 

Yeah basically. I drove his truck and when we were going slightly uphill at low rpm it would shake really bad. If you have a misfire, you should feel it.

 

Mine sounded like a drag car. Knew it right away

sent from area 51

 

It shouldn't make it louder unless you shot a plug?

 

I didnt blow one just chugged like a drag car

sent from area 51

 

My truck has been misfiring for about two months now with no CEL at all. To find out for sure you'd have to get a diagnostic scanner.

Out of all 8 coils, two of them were toast. I could tell when I inspected them individually. The condition of the boots and springs were gone, and these were aftermarket coils that the previous owner had installed.

 

The whole truck will shudder during acceleration. That's what happened to me, and that's what my service advisor mentioned. I had another independent mechanic check it out and he said he can tell it was misfiring just by the way it sounded when he revved my motor. I can't tell s**t because I'm partially deaf. But a lot of owners will think it is a transmission related issue, which is what I thought it was originally.

Yup, that's what it felt like to me. I felt like some fat chick was sitting behind me trying to nibble my ear and I had to push the b***h away.

Some well experienced technicians can tell it is misfiring by the way it sounds during idle and during mid-RPM revs.

 

Here is a video of me revving my motor after I replaced the ignition coils. I didn't take a before video so you can't really tell that it was missing. The motor revs smoothly and the idle is clean. Before the second rev, I rolled down the windows in case you're wondering what that screeching sound is. Also, the exhaust is courtesy of Borla.

http://s1208.photobucket.com/user/Lyosha/media/Vehicle Projects/M4H00001_zps84acb438.mp4.html

 

well i can say i'm not missing or anything when driving but i can tell my plugs need to be swapped. just takes longer to crank until it turns over, doesn't sound healthy when it starts.