okay so my cylinder #5 was misfiring i code scanned it and its what popped up so i replaced coil pack, and its been great for 3 days engine light went away on its own. and now 3 days later my rough idle is back engine light is back on..code read it and #5 is misfiribg again?.. what could the problem be..bad spark plug? or maybe i changed it in wrong order #5 is closest to firewall right? any help please

 

What engine are we talking about? I5 or v8?

Could be a bad coil ground, cracked/damaged insulator on the plug, damage to the coil durring install.

Incorrect gap etc.

Start with the basics, pull the plug and inspect it for damage, and check the gap.

Check for rodent damage, heat damage, or rubbing on the coil harness.

Had a mouse build a nest around my #1 myself on my I5.

 

its the i5 engine 2008... me being to excited i didnt even check my spark plugs i guess ill have to do that first..hopefully the new coil pack isnt damaged and its jyst the plug i dont wanna have to spend another 80 bucks on a new pack..will update when i pull the plugs

 

k replaced all plugs and still misfiring?? all wires and pack is good wtf any help

 

Replaced under warranty at 58k. I'm coming up on 75k. I hear this could happen again based on what I have read.

 

So it could be the head gasket? Im just trying to figure this out before i have to bring it to a shop to get ripped off. I figured with the obd2 reader it would tell me the exact problem. And all its saying is cylinder 5 misfire. I dunno everything checks out good one guy told me i could be a gummed up injector? Hopefully i can get this figured out

 

I mean cylinder head not head gasket. I hope its not that, i thought that problem was solved before the 08's mine is a 08 h3 3.7 i5 with 140,000 k's

 

the misfire only happens in park or at a long stop light idling in drive but other than that while driving it is perfect..if i set the idle higher would this possibly eliminate the idle skip

 

you really need to check your spark plug. spark plug can tell u a lot about the cylinder just by looking at tip, black not burning gas properly, white chalky: lean, oil piston rings, does it takes time to start? stop and pull spark plug out check for antifreeze on spark plug if start check also exhaust pipe after warm for water or vapor with funny smell like (antifreeze). also with motor cold open radiator cap and start u engine and check for steady bubbles the last two would tell if is head gasket. try to take pic of spark plug to see if we can help.. hope is not head gasket

 

spark plugs are brand new oem plugs, and the old ones were half decent, either way same exact thing,..it starts and drives like brand new, just when stopped for awile is when the misfire happens and engine light blinks, there are no smells and no leaks coming from anywhere other that that it is mint, it just is weird that it does this after a while on long stops?