installed a new set of MSD wires and now every couple seconds is a pop or puff sound. It doesn't do it when i hold the revs higher than idle.

Could it be a bad wire?

Not sure what else since it's all i touched/changed.

 

Take them back and make sure they give you some other ones and make sure they are the right ones for your ride. I had a buddy who had the same thing happen in his Civic. He put new wires in and it was popping and missing for a while. He took them back and it turns out they had given him the wrong ones. He put the new ones in and it ran perfectly.

 

I doubt you have a bad wire. You may have one not seated all the way on the opti or on the plug. The ends on the opti can be hard to insert correctly. I'd start by just rechecking your work, wire by wire and make sure they are all on the right terminal and pushed in all the way. If you did plugs, make sure you didn't crack any of them. You got a missfire from something you did. Also, when you redo all your connections, use some dielectric grease on the connections - it seals them up and helps them slide on and off.

One other remote possibility is that you have the 5 & 7 wires crossfiring. I doubt it's that, but make sure those two wires are not tied together running parallel cause that can cause problems on a chevy.

 

I do have some of the wires zip tied together. So i can't have any of them touching each other at all?

Can i have them touching or resting on any body metal part? i do have #8 run around the passenger header along the fender well.

 

its not a good idea to have your plug wires tied together or resting on metal..

i would almost bet you have one end or the other of a plug wire that isnt connected properly... new plug boots can be difficult you need to make sure the plug wire is all the way to the end of the plugboot, if it isnt you could put the wire on and think its seated when it isnt actually clipped on the tip of the plug

 

Yeah, that's true. If you've ever touched the plug wires on a running motor, you would know the rubber doesn't insulate the current too good.

Yes, I've been shocked by a few 2 stroke outboard engines.

 

I agree and doubt that the wires are bad. I did a little test last night and found two of the header primary tubes are not getting as hot as the others - #'s 1 & 5 i believe they are. Thankfully the ones right up front on the drivers side which are the easiest to get to. I pulled the plugs and am going to replace them tonight - maybe they are cracked?

I'm almost positive the boots were on tight for these as i heard them click on.

The other thing that i find strange is it's only at idle that it pops and after about 5 minutes . If i hold the revs up higher - even just slightly - it's fine.

 

Out of curiousity is there any chance that maybe one of the plugs needed to be gapped again, and the new cables exposed that?? I dont know too much about all this it is just a guess. But is it possibility or no?

 

I checked that and they were still at .050.

I'm really hoping the new plugs will put this to rest.

 

well im sure that it will help Ive heard of cables causing the same issues your having.

 

Opti ends too??

 

yes i checked that the boots at the opti were tight too. I mean there is no way i could push them in anymore. Plus i heard the double 'click' they make when connecting to the terminal.

 

Checkout the coil wire, mine would pop too, turned out to be the culprit.

 

I seemed to have fixed it!! Replaced the two plugs and bingo!! No more misfires - thank god!!

thanks to all for the help!