P2098 & P0517 codes

I can't help with the hot battery issue but I fought a 2098 code for a long while. Ended up replacing the downstream O2 sensor, tightening the manifold and upper cat bolts good and switching fuels. In addition, changed out plugs for another issue, cleaned TB/IAC thoroughly and put it all back together. I clean the TB/IAC as part of my routene maintenance now every plug change at around 25K miles. With tightening the manifold bolts and upper cat bolts frequently after every wheeling trips, and the fuel change, I haven't had the 2098 return since. That's been a couple years now. I did NOT need to change out the lower 02 sensor as I've since switched the old back in (just out of curiousity). I believe the bolt tightening and fuel swap was what did it. Before, I had been running ONLY safeway or Costco gas. It is cheaper and I got the discounts. After noticing BOTH my Jeep AND my '07 Subaru having fuel relating running conditions, I started looking into it further. As a result, found both Safeway and Costco, as well as a couple other low-end fuel places in town all get the same fuel from the same supplier. Would you guess that it's Low Tier fuel and does not have all the cleaners/additives in it that the regular top tier fuel has? After cleaning, and switching to top tier gas-strictly Chevron, Texaco or Shell, I haven't had the issue in EITHER vehicle since-and it's been a few years now. After cleaning again, BOTH vehicles have been very clean inside without the issues since.

Hope that offers some assistance.

Best of Luck,

Mike

What year is your rig? Mine is an '05 and I actually have 3 cats-two upper mini cats and one lower cold 3rd cat. The two uppers are monitored while the 3rd is not. There are two upper O2 sensors PRIOR to both mini-cats up top, with 2 post cat O2 sensors after each of them. The one I replaced was the last one in line (I think) on the horizontal pipe just prior to the 90 bend heading below the oil pan before it makes another 90 down to the 3rd cat. Hope that makes sense. The sensor is on top of the pipe and pretty easy to get to. You don't need any special wrenchs or anything-at least not on mine. Forget the size-maybe 3/4" open end wrench??? It's been a while since I changed it out. You'll see it immediately when you crawl under there.

As to removing the cats-I have tested my exhaust a fair amount with running the total complete stock exhaust, stock exhaust minus factory muffler with high-flow spintech replacement muffler, factory upper cats minus 3rd cat with spin tech, clogged front upper cat with open secondary (back) cat, no 3rd and spintech, full new cat replacement including 3rd cat and spintech and I forget what else. I currently have both new upper cats with new 3rd cat as a full cat replacement from Eastern Catalytic and the spintech. As it runs now, I will be removing the 3rd cat as soon as I get the necessary stainless fittings to fit a section of strait pipe (good suggestion from a member on the board here-thanks BTW). Will remove the 3rd again and run only the two uppers with spintech.

While I am NOT avocating the removal of the third, or directly telling anyone to do it-check your state laws prior to removal, what I WILL say is there is a definite gain to be had (at least on MY rig with MY testing), I will say this-If still running stock total exhaust with stock muffler, the biggest gain to be had with exhaust work is to remove both the stock muffler and the 3rd cat and replace with strait pipe back to a high-flow muffler. It's a little louder than stock but is not overly obnoxious with trail use. I HATE obnoxiously loud mufflers on the trail and like to be able to idle without issue and hear commands from spotters on the trail. This is about as loud as I'd take it while still being "trail friendly" if that makes sense. Having put the 3rd cat back in for testing-this is a brand new cat by the way-I did lose both mileage and performance with the install of the 3rd. I do wheel hard, DD use daily and tow hard as well so I DO Know the difference. I WILL be removing the third again and running strait pipe to spintech as that setup FOR ME yielded the best engine running conditions, best mileage, best power/performance, best towing, best DD use, etc. I was happiest with the running performance with that setup so I will go back to it.

AGAIN, NOT TELLING ANYONE TO REMOVE THE THIRD-CHECK STATE LAWS PRIOR TO REMOVAL!!! This is just MY testing on MY rig-and a few others in town, that work well.

Sorry for the "eco friendly" stuff there, just was scoulded on another board for admiting what I've done. Use discretion and proceed with caution... :lildevil: :rotflmao:

Hope that helps.

Best of Luck,

Mike