Are your cats clogged?
Edit: you’ve gone this far, don't turn a blind eye to properly doing a vacuum leak test.
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Engine hesitation
- Thread starter RicanCrazy
- Start date
Are your cats clogged?
Edit: you’ve gone this far, don't turn a blind eye to properly doing a vacuum leak test.
That's the last part I'm saving due to needing someone to weld a new one on. (Not experienced enough to do it myself).
You can drop the exhaust some and run a bore scope inside to check, or check using a scope from the tailpipe. (sorry, can’t remember the cat configuration on your year).
Added an edit to my last post that I think is important.
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99 tj has only the cat down by the skid plate. But the disconnect is next to it so I'll check it out. I don't think it's the cat, it's not throwing any codes. And I've seen on plenty of vehicles that the moment the cats go bad they show codes and other things happen.
Not saying it is the problem, but I believe it's worth verifying at this point.
FWIW, I had a bad cat, and I didn't have any codes.
The catalyst inside would move around and sometimes plug up the flow preventing me from accelerating.
I had a shop review the cats when they replaced my freeze plugs. The shop said the pre-cats were good. I took a look just to be sure, and one was definitely loose so I replaced it all (solved the issue).
Make sure you wiggle/vibrate the cat when you have it off to ensure it's not loose.
You might even consider driving the rig with the cat removed to see if it drives better.
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Final update. The throttle body I ordered last week came in. Installed it and my issues vanished. Even the RPM ( assuming the leak at the lever was giving it too much air and made the rpm bounce up and down 200). I hope this thread finds people that come across the same issue I had because it surely wasn't available when I needed it lol. Thanks again everyone that gave advice and input. It was greatly appreciated! See y'all when something else breaks! 
Final update. The throttle body I ordered last week came in. Installed it and my issues vanished. Even the RPM ( assuming the leak at the lever was giving it too much air and made the rpm bounce up and down 200). I hope this thread finds people that come across the same issue I had because it surely wasn't available when I needed it lol. Thanks again everyone that gave advice and input. It was greatly appreciated! See y'all when something else breaks!
Congrats man glad you got it all buttoned up
Final update. The throttle body I ordered last week came in. Installed it and my issues vanished. Even the RPM ( assuming the leak at the lever was giving it too much air and made the rpm bounce up and down 200). I hope this thread finds people that come across the same issue I had because it surely wasn't available when I needed it lol. Thanks again everyone that gave advice and input. It was greatly appreciated! See y'all when something else breaks!
I need one too,do you have a link to the throttle body?thanks
FWIW, I purchased a used TB and a new BBK TB and both had bad vacuum leaks at the ends of the butterfly valve.
I did what I wrote in post #37 for about $10.00 and have been leak-free.
BBK 1724 62mm Throttle Body - High Flow Power Plus Series for Jeep 4.0L https://www.amazon.com/dp/B001GBRIKW/?tag=wranglerorg-20
Unfortunately the issue slowly came back after two weeks of driving fine. At this point I'm completely stumped. I've meticulously checked every vacuum line from intake all the way to box and fire wall. Every sensor under the hood has been changed, spark plugs, wires, distributor cap and rotor and sensor, ignition coil, and throttle body have been all changed. I'm not sure what else to check or even change at this point. Still absolutely no check engine codes are popping up either. I'm eventually going to have to take this thing to get diagnosed and maybe hope its not an actual internal engine issue.... 
So I believe I can finally conclude the issue has been found and fixed. I spent the extra couple dollars and got the Mopar tps sensor to replace the cheaper one I got. While I was at it I checked the temperature sensor above the thermostat and the plastic connector free spins on the brass piece ( don't think it's supposed to do that since the new one is solid and doesn't spin) so replaced that at the same time as the tps. She idles smoothly and gets up and goes when needed. It has also cured my rough idle and my rpm jumping while going 40-55. So in conclusion to this whole situation, just spend the extra money for oem/Mopar, and two, even if your smarts thinks a part may not logically contribute to an issue... If it's cheap enough just change it out.... 
Atleast I know that everything under the engine is new minus the engine it's self ( have parts sitting in the house to tackle oil pump, rear main seal, and valve cover gasket for a later project).
Atleast I know that everything under the engine is new minus the engine it's self ( have parts sitting in the house to tackle oil pump, rear main seal, and valve cover gasket for a later project).Similar threads
