Just a quick note, not a solution, I have an 08 jk, six speed, CAI, stock exhaust and superchips mid range tune (91 octane I think). I run 87 octane have no problems with ping, definitely have more power (seat of the pants, but noticeable none the less). I may have picked up 1 mpg as well. Need to run more tanks of gas through it to
confirm. I don't think your CAI is causing any problems. I have stock air box if you really really really want to try it. (Canada by the way). Only ever had ping when I ran 95 or 97 octane tune on 87 octane gas. It sure was a lot of fun but had mild (yes MILD) ping, so dropped it back. There would appear to be something very wrong with your PCM yet no codes ?. The superchips programmer will read and reset codes for you. My 2 cents

 

Canadien fuel uses the same R+M/2 Octane method as we do in the states. I'm sure they get into the cheaper winter fuel a couple weeks quicker than we do, perhaps September 1 it starts getting delivered.

The EGR check up is a good call. It could definitely be the culprit despite not throwing codes. It's also dealing with 30% less exhaust gas density because of the 3" pipe. Not sure it's the culprit, but another case of where changing mechanicals totally screws with a properly functioning PCM, sensors and valve controls which are table based and expecting defined results. Hence no codes but not recirculating enough exhaust gas.

There have been quite a few people who have had EGR issues and codes with less than 40,000 miles. If you have carbon build up in the cylinders you assuredly would have it in your EGR valve. Erratic opening and closing of the valve goes a long way in explaining why other prescribed fixes have modest success but don't alleviate the issue.

Mark Doiron had a write up on how to replace the EGR Valve revealing a much easier way to get it done than what is in the service manual. Removing the inner fender liner and doing it from the side as opposed to trying to do it from the top. You might even be able to simply clean it with some carb cleaner or the like and scratch it off your list for the cost of a gasket.

I'll post the EGR write up after I find it.

https://www.jk-forum.com/forums/show...&highlight=egr

 

The stock airbox isn't going to help him...he has bigger issues

 

You can simulate the restrictions of the stock air box with a plastic bag, a 3" hole cut into it, and attach it to the current air filter. Not likely in itself the answer, but part of the root cause is more air than the fuel delivery requires.

 

You're right. The service manager told me for warranty purposes I have to run two tanks through it before they dig any deeper.

 

If it actually is carbon build up in the EGR valve, that stuff would take a fair amount of time to work through, if it were to work at all.

I'd also be concerned about just how far Chrysler will go in resolving your issues. You have two things that could be attributable to your issues, the CAI and exhaust, and a thrid in the Superchips programmer they likely don't know about. Then there are the extra load placed on your JK with larger tires. Add it all up and you better be bringing the doughnuts the next time you visit the dealer.

 

Found a new noise coming from the bellhousing watch the video and let me know what you guys think.

http://s1198.photobucket.com/albums/...t=IMG_2728.mp4

 

Thanks for the offers for the stock air boxes but don't think it's worth the trouble

 

No you have a bigger problem. If you are using a programmer some of those tunes are notorious for causing spark knock. Honestly I would run the 2 tanks like the dealer recommended, and drive it pretty hard. If it doesn't help....take it back and let them do what they need to do. Just find out exactly how they are fixing it

 

x2 ... get back to basics.

The tune, superchips (or whatever it is), CAI and 3" exhaust needs to go. Mother of God, 3" exhaust on a 3.8L motor. Although, when I asked these questions earlier, he said he's running the stock tune.. but I wonder if that's the case.

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