Kj bad resonator sound but no resonator???

Eric120daniel

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This is a separate thread to my original question. I have a 2003 jeep kj I’m trying to hunt down my bad mpg problem (original post below) I’m really thinking It’s a bad exhaust because I’ve been doing research and had no idea a bad exhaust can cause horrible mpg(my original problem) and a misfire( got a random po303 yesterday cleared it and it hasn't come back)

I'm planning of fabricating an exhaust but my problem right now I hear what sounds exactly like a bad resanator when I give it a little gas with my door open. Everyone says the KJ’s only have a third cat which it doesn't sound like a bad cat at all. Is this just a cause of a bad muffler I haven't heard before or is there a hole on the y pipe? Could it be a resonator after all? I can't find a definite answer. The muffler doesn't sound like it's rattling but I have seen exhaust smoke shoot out of the inlet ****** when it was cold out. Is that my issue? If it is a cat I actually be more excited because it will hopefully pay for my new muffler lol. Also if anyone has taken that part of the y pipe out would you please share how you replaced it. I hear everyone goes with the Magnaflow but I wanted something more like a Catback but don't want to pay for the 200+ one so I figured I'd just make my own.
Video (sorry it's a short)
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Skipperau

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Sounds like a hole in the pipe, somewhere pretty high up, near the Cat? Check to see if your O2 sensors haven't come out for whatever reason. Your thought that your bad mileage could be related to the exhaust could be right, but you need to chase down all of your issues in a sequence because they all relate to how it runs. So, do your plugs, look at why the PCV hose is collapsing (due to vacuum) and fix/replace your exhaust and I'd think you'll go a long way towards fixing your issues. Once you've done them then it'd be chasing the smaller stuff.
 
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Eric120daniel

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Sounds like a hole in the pipe, somewhere pretty high up, near the Cat? Check to see if your O2 sensors haven't come out for whatever reason. Your thought that your bad mileage could be related to the exhaust could be right, but you need to chase down all of your issues in a sequence because they all relate to how it runs. So, do your plugs, look at why the PCV hose is collapsing (due to vacuum) and fix/replace your exhaust and I'd think you'll go a long way towards fixing your issues. Once you've done them then it'd be chasing the smaller stuff.

Yeah my plugs had oil foul and where not tight either. Bought some heater core hose and am running that right now it still looks like it's collapsing but no parts stores sell good a pcv hose for the valve so Ill have to order a oem part maybe from mopar to fix or Ill pull one off at the salvage yard when I get my coolant tank. I cleaned my valve out with brake clean even though it was already rattling. I'm assuming that there's probably a hole in the pipe but I'll check my 02 seniors as well. I live in the midwest so I'm sure it's rusted through as almost everyones is lol. But the idea of doing a aftermarket exhaust won't leave my mind now so I'll probably end up doing it.
 

turblediesel

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A good way to check for exhaust leaks is to have an assistant block the exhaust outlet momentarily with a *** of rags while you listen for leaks along the exhaust system.
 

tommudd

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No third cat on your 03
more then likely small hole in rear part of muffler
No need for a two hundred dollar cat back, just did a kids 04 the other day and I had less than a hundred in it , charged him 25 to do it , cheap I know but the kid ( well 27 years old, that is a kid to me ) is trying to do things right and learning as I show him things
as far as oil soaked spark plugs that is a whole other issue with more than likely bad oil seals on the valves or just excessive engine wear
 

Eric120daniel

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A good way to check for exhaust leaks is to have an assistant block the exhaust outlet momentarily with a *** of rags while you listen for leaks along the exhaust system.

Yeah I might give that a shot or I’ll just wait till winter again and see if I can’t see exhaust smoke coming from the leak again. I’m probably not gonna fix it until I get the oil fowled plugs figured out.
 

tommudd

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Yeah I might give that a shot or I’ll just wait till winter again and see if I can’t see exhaust smoke coming from the leak again. I’m probably not gonna fix it until I get the oil fowled plugs figured out.
Yes , go ahead and wait , its a good way to get carbon monoxide poisoning
so why do it now LOL
 

Eric120daniel

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No third cat on your 03
more then likely small hole in rear part of muffler
No need for a two hundred dollar cat back, just did a kids 04 the other day and I had less than a hundred in it , charged him 25 to do it , cheap I know but the kid ( well 27 years old, that is a kid to me ) is trying to do things right and learning as I show him things
as far as oil soaked spark plugs that is a whole other issue with more than likely bad oil seals on the valves or just excessive engine wear

Yeah I was planning out how I wanna gonna do an engine living with only street parking but I did a compression test and I got around 170 on all cylinders. Wish I had hooked up a jumper pack because it was cranking slow near the end of the test but the cylinders with plug fowl where good. It’s either an issue with the pcv which I’ve been fighting with for two years now or my test was bad who knows. Yeah I’m not gonna buy the 200 dollar one I would buy things to fabricate my own. Idk it would also be cheaper and easier to just put an oem muffler on it too and call it good I’ll see what i wanna do. I just just get my return and I got 400 back so I have a little money to play with.
 

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