Changed Plugs, Now Bad Idle
 

Ok so yesterday i changed my spark plugs. no big deal, the old ones came out fine and looked like normal used spark plugs should. except for one of the trailing plugs. on the tip where the wire would click on to the plug it looked all corroded and rusty, and when i took the boot off of the plug the wire boot just kinda fell off.

so i put the new plugs in and turned it on and it seemed fine, after a day of driving it idles like its missing slightly, now i think that the wire for that one messed up plug was on its way out and when i put the new plug in it killed the wire or something.

as far as the tip of the plug is its like white on one half and black on the other, the other trailing plug looks like this too, so it seemed normal.

I pulled the plugs and checked them, they look normal, made sure all the plugs and wires were in the right postion as well.

I tried leaving that one trailing wire off the car and starting it it seemed to be slightly worse but not by much, my best guess is that the wire is bad and is just giving really weak spark if any at all.

Im pretty sure that this is the problem but i want some input before i go buying things, if maybe something more serious may be wrong from what ive explained. ive never changed the plugs on a seven before so i really dont know if this is like normal or anything, im sure its not but, thanks for any help

If they are OEM wires and have more than 60-75K on them they probably need changing anyway.

Bt make sure they are on all the way. Often times the plug wires do not get slipped on all the way and that can lead to misfire (more often at idle than any other time).

Well, this is definately A problem at least.. It might not be THE Problem, but I would start with replacing all of the wires. Crap wires lead to crap combustion, and if that one wire sucked that much, you can bet that others are near that bad, or will be soon. My experience: Don't go with the cheap store brand wires (like Exxcell, or whatever its called), spring for the NGKs or something name brand. I had a few Excells just fall off of cars before..

i was going to get MSD wires, i saw a set for about 50$

There is no real advantage to using expensive wires like the MSD or Racing beat over mid priced wires (like Jacobs, or NGK).

well i dont know, i just was looking around and saw that they were direct fit

www.summitracing.com sells OEM NGK wires for less than $25 with free shipping last time I check. They dont have it listed on the website but call them and they'll tell you they can get it.