I just had a Magnaflow catback installed. The directions said to disconnect the battery prior to installing it, so the computer could reset itself with the new exhaust installed. The muffler shop did not disconnect the battery. I feel like the Jeep is lugging down when it's on the freeway. It just doesn't feel quite right. So I'm thinking maybe I should disconnect the batter now and see if that makes a difference. So what is the procedure for disconnecting the battery? Do I disconnect both the positive and negative terminals, or just the positive, or ??? Which one do I hook back up first or does it matter? How long am I supposed to leave it disconnected? I think I read somewhere that disconnecting the battery can put the Jeep in limp mode. I certainly don't want that, so I need to know the proper way to do it.

 

Just disconnect negative terminal for 30 mins.

 

Read this.

https://www.jk-forum.com/forums/show...ighlight=reset

 

and make sure that you have shut your motor off before you do

 

This is why I'm confused: Some people say to disconnect the negative terminal only, others say to disconnect the positive terminal only, and some people say to disconnect both the positive and negative terminals. And then some people say to reconnect right away, while others say wait 30 minutes before reconnecting, and still others say to wait an hour. I checked my manual and can't find anything that tells me the correct procedure.

 

Yo, is this when pulling the trailer ???, also it will take the PCM module a bit to adjust for the better air flow, BTW how does it sound ????? any clips???

 

It's not absolutely mandatory that you disconnect the battery; it'll just take longer for the computer to adapt to the new exhaust. If you do decide to do it, only the neg side is needed. 10 minutes should be fine.

 

I have not pulled my trailer yet since installing the Magnaflow.

My JK drives different and just feels a little off since installing the catback. Off the line, it has a nice power boost, but once I get up to speed, it seems like it shifts into 4th too soon and then lugs. Yesterday on the freeway (completely flat section), I could hardly use overdrive. It kept wanting to shift back and forth from 4th to 3rd to 4th and the rpms seemed lower than before. When I pushed the overdrive off button, it drove much better. The way it is driving, it makes me think once I do hook up the trailer that I'll be stuck in 3rd gear going down the freeway, where before it towed just fine in 4th with overdrive off. Keep in mind that I just have the stock tire size and 4.10 gears.

The exhaust does sound great--no sound clips. I'm hoping that the computer adjusts soon, because it's driving me crazy!

 

the way I see it coming from an electrical field is it does not matter you are talking about a dc system so either will work. The only thing I can think of by diconnecting the battery while doing the exhuast is when welded it up to not create a spike in the electrical system. all it take to reset your computer would be to disconnect it for min 30 seconds.

 

If the PCM is anything like the one in my Magnum, and they should be because they're both Chrysler, all disconnecting the battery does is speed up the process. It has to "re-learn" the engine parameters. Leaving it hooked up does the same thing; it just takes longer.