Been a quiet reader on this forum for years. Jerry, you and the rest of the TJ community have provided so much great info! Thanks. Time for the exhaust to be replaced on my 97’ 2.5l. Manifold was done a while back due to crack. O2 sensors are new and PO deleted catalytic converter instead of getting cat converter recall work done…..actually still is listed as incomplete with Jeep dealer. Doubt they would replace the cat when its not even there anymore…..real question is….do i replace down pipe and back with walker everything including Cat? Or do i leave the cat out, replace with a straight pipe, and use o2 sensor bung spacer (just on sensor after cat)?? My tj is bone stock and i love it that way. Since replacing the o2 sensors, CEL (o2 sensor code) was gone and then came back within 20-40 miles now with P0420 for the cat. MPG has always been around 15 or so but now has dropped horribly to under 10. Just looking to get back to the 15 mpg and most importantly, do the best thing for the engine and longevity.
Exhaust system replacement questions
- Thread starter cfabes
- Start date
Been a quiet reader on this forum for years. Jerry, you and the rest of the TJ community have provided so much great info! Thanks. Time for the exhaust to be replaced on my 97’ 2.5l. Manifold was done a while back due to crack. O2 sensors are new and PO deleted catalytic converter instead of getting cat converter recall work done…..actually still is listed as incomplete with Jeep dealer. Doubt they would replace the cat when its not even there anymore…..real question is….do i replace down pipe and back with walker everything including Cat? Or do i leave the cat out, replace with a straight pipe, and use o2 sensor bung spacer (just on sensor after cat)?? My tj is bone stock and i love it that way. Since replacing the o2 sensors, CEL (o2 sensor code) was gone and then came back within 20-40 miles now with P0420 for the cat. MPG has always been around 15 or so but now has dropped horribly to under 10. Just looking to get back to the 15 mpg and most importantly, do the best thing for the engine and longevity.
Welcome to the forum. I don't want to hijack the OP's thread, so @Chris maybe we should make a new one for @cfabes.
In case it's helpful, you may benefit from the either the 97 thread or the SE thread in my signature line.
See also my build thread for notes on my recent job of replacing the entire exhaust system on my 97 SE.
Just sending a quick reply to maybe "bump this".....anyone got an opinion or experience that they'd like to enlighten me with?
Agree, a 4.0 without a catalytic converter smells like a 1950s carburetor V8. I've also never seen a noticeable gain in Torque or HP, but a yes to mpg drop, my suspected cause with that would be less back pressure, incorrect O2 measuring.
Hahaha…..I dont know any different since its been that way since i have owned it. But i have always thought it was loud and fumey…..walker quiet flow muffler and the rest of their system is what i was thinkin of installing
Thanks for the input. I cant imagine their would be any power gain or similair ‘performance gains’ when my lawnmower has more horsepower than the 2.5l i have….hahaha
Yeah you really can't go wrong with that. I've put a few of their systems on Jeeps over the years and for the price they bolt up and fit nicely. Painting it with a little high heat paint before install can also make them last a bit longer.
Was not been happy with the Walker SS on my 2.5, had 2 of them disintegrate rather quickly and I will not install another one. Seems the SS designation is internals only. This is what I installed almost 4 years ago (12/19) and it's really SS and it's also available with the flange for the oem Cat arrangement.
https://www.napaonline.com/en/p/EXH21337?impressionRank=5
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If you are not looking to break the bank I recently got the following:
https://www.ebay.com/itm/1997-2000-...d=link&campid=5337789113&toolid=20001&mkevt=1
It seems to be decent quality and made in the US.
https://www.ebay.com/itm/1997-2000-...d=link&campid=5337789113&toolid=20001&mkevt=1
It seems to be decent quality and made in the US.
Thanks for the input. Looks like it is only the muffler and tailpipe…..I’d still have to get a cat and down/front pipe
Is the link to just the muffler or does Napa have the rest of the system available too?
You will continue to throw the P0420 Cat efficiency code until you install a catalytic converter. What were you fuel trims at prior to replacing you O2 sensors vs. what they are reading now?
Being that you replaced the O2's, you can perform a global reset, Just disconnect the +/- battery cables from, the battery and hold them together for 30 seconds. This will drain all the power from the capacitors in the ecm basically causing the system to relearn everything.
Being that you replaced the O2's, you can perform a global reset, Just disconnect the +/- battery cables from, the battery and hold them together for 30 seconds. This will drain all the power from the capacitors in the ecm basically causing the system to relearn everything.
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