Popping exhaust after new plugs and air filter

boaterdave90210 · 06-24-2012, 09:20 AM

I have a 99 wj with a 4.0. I took the air filter out to clean it and re-oil it, and while it was drying, I replaced all the spark plugs. When I put the cap thing back on the spark plugs, I made sure it was secure, and then tightened it down. After that was finished I put the newly oiled air filter back on and started it up, drove it about a mile and then back home. Thats when I noticed the check engine light and the exhaust popping with no rhythm. Any thoughts on what this could be?

**rcwj04** · 06-24-2012, 09:31 AM

It's a misfire, one of the boots is not seated on the spark plug properly, same thing happened to me

MuddyWJ · 06-24-2012, 10:22 AM

^x10

**86cj74.2L** · 06-24-2012, 01:04 PM

Or their not in the proper order read the codes and it will tell you which cylinder to look at

**rcwj04** · 06-24-2012, 01:50 PM

Quote:

Or their not in the proper order read the codes and it will tell you which cylinder to look at

Its kinda hard to mess up the order considering its a coil rail, but I guess anything is possible hahaha

**86cj74.2L** · 06-24-2012, 02:15 PM

Do the on off on thing three times and see what misfire code you got. I keep forgetting their wasted spark now.

It's not the first time there was a bad plug in a new box.

Or put your old plugs back in and see if it goes away.

Is the check engine light flashing? Or on solid?

**billzcat1** · 06-24-2012, 03:14 PM

What plugs did you use? Remember the 4.0 is picky about plugs...

boaterdave90210 · 06-24-2012, 07:24 PM

I pulled off the rail, put it back on and it worked fine! I guess it was just picky :P Thanks guys!!