Thread: urgent need help misfire

well i never swapped back the coils and lastnight i had a slight miss in the gt. no codes. took the gtp out tonight on a very spirted ride. couple say 30 to 80mph runs. no miss. but it seems to smoke a lil bit and it smelled...

That's not good.

BTW Nacho... if you can stretch a #3 wire to fit in the #6 position, I'll be impressed.

Sorry I read that wrong. Reread and it doesn't work the way you are thinking though. If you swap the wires and the misfire doesn't move, it still means the ICM might not be firing the coil when that cylinder should fire. If you add the changing coils and the misfire doesn't change, you've done wires and plug, then it's either an injector or the ICM isn't firing at the time for that one cylinder. It's more common for a coil to die, but I have seen the ICM fire for say the #3 and not the #6

[QUOTE=BillBoost37;699116]That's not good.

QUOTE]

sooo what are you getting at Bill?

not sure but thought i would add. i feel like it takes a couple extra cranks for the car to turn over. what the phuck is wrong with my car??? ughhhhhhhhhhh

If we know the coil is good then we have ICM, plugs and wires. The swapping of the wires on the coil is to see if we can get the miss to move to the companion cylinder and eliminate the non ignition parts.

Nacho..
You say if you know the coil is good, you are trying to rule out plug or wire, even injector by swapping the wires. It doesn't work that way. If the miss moves and all you've changed is the tower on the coil, then it's the coil. When you move a piece of the puzzle say injector and the miss moves with that injector, then the problem is the moved part.

By changing only the coil post on a good coil, you aren't ruling out anything because you haven't changed anything except from one good tower of the coil to another. That's how I was reading it. Maybe I'm not reading it properly?

Originally Posted by BillBoost37

By changing only the coil post on a good coil, you aren't ruling out anything because you haven't changed anything except from one good tower of the coil to another. That's how I was reading it. Maybe I'm not reading it properly?

If the misfire moves to the companion cylinder we have now established that the misfire is ignition. We have ruled out non-ignition components.

This car comes in with a #2 misfire. Lets say that the ICM is firing #5, the companion cylinder, but not #2 ,but we don't know the ICM is the cause. We swap the coil with another coil. The miss doesn't follow the coil, #2 is still a miss. We then swap #2 wire with #5 wire at the coil. Now #5 is a miss and #2 fires. We just ruled out non-ignition components.

My next step is I replace #5 spark plug wire with a known good wire. I keep some known good wires on hand for stuff like this. If that doesn't fire #5 back up I then run a known good wire to #2. If that doesn't fire #5 back up I pull #5 plug and if it looks good I swap it with #3 to see if the miss travels to #3 with the plug. If it doesn't, I then swap#2 plug with #1 plug to see if the miss travels with the plug to #1. If it doesn't go to #1 then I try an ICM.

I apologise if this seems like thread jacking but I'm trying to help you diagnose your miss. This is just a quick easy thing that you can try with minimum tools and diagnostic equipment.

It can also help to explain to you (OP) and others how those of us that find things pretty quickly do it.

You kinda lose me at the swapping of the wires on the car. Because none of the front wires are long enough on our cars to reach to the back cylinders. Therefore if you move the coil and #2 is still the misfire, swapping the wires at the coil only was how I was reading it. Which of course if it's a wire, that wouldn't typically show any change as the icm/coil will still fire the companion #5. I do agree and have some wires on hand as well. Swap out a wire and if the miss goes away, it's wire. Stays, swap a plug and if it doesn't move then it's possilby ICM or injector. In the end..I believe we are both saying the same thing. I was just a little confused with how I was reading into it.

uhmmm soo how bout that burning smell? you just gonna say "thats not good" and leave it at that? i feel like my thread haz beenjaked

We can't magically diagnose everything over the internet. You are going to need to lift the hood and look for leaks/find the smell etc. You beat it a little, it smoked and smelled. From where?

FWIW we aren't jacking your thread. We are discussing ways to try and help you diagnose it further. If you'd like us to stop, we can.

Originally Posted by BillBoost37

We can't magically diagnose everything over the internet. You are going to need to lift the hood and look for leaks/find the smell etc. You beat it a little, it smoked and smelled. From where?

FWIW we aren't jacking your thread. We are discussing ways to try and help you diagnose it further. If you'd like us to stop, we can.

nah bro it aint that im just getting lost with "cylinder 2" and stuff and im just triena get an idea some / what thing where to look / do amd got lost. sorry haha. i need a scanner . i get sketched swappin plates to drive 3 miles up to the zone. polease most deff dont stop