askingxforxit

Have brand new sensors, all four. No I haven't checked the manifold bolts yet but I'll put that on the list.

askingxforxit

I can't seem to find a replacement for the pre cats. Some auto parts stores specify that they are for after 1/20/2000 mine was manufactured in 7/1999 but is a '00.

bsmith97xj

Your fuel doesn't have ethanol in it by chance? Maybe get fuel from a different place.

askingxforxit

I don't believe so. Been using the same gas stations for almost a year now.

askingxforxit

Exhaust only smells after its been run and at normal operating temp. Idle at cold start is also normal

Jesse Hallum

Be sure the problem is cat failure --CA carb-mandated units are extremely expensive, and you will probably have to go with OEM units, which run will run you about $2400 for the set.

OEJ

dude ur problems the bosch sensors. Any after market o2s will burn out in our 97-01s. the sensing probes are to long and practically touch the inside of our down pipes. missing it by maybe 1/16".U need to go to the stealership and buy Mopar 02s only.

I went through this a year ago. i went through 3 02s and then got a mopar. took the aftermarket and the oem and compared them. the bosch's probe was longer than the oem 1. explained this to the master mech at the dealer and he said thats been a problem for the 97-01 cherokees.

askingxforxit

Thats what I was afraid of. Thanks man

askingxforxit

I've read that before but after I had already installed the bosch. Hoped I would get lucky. Previous to the bosch I had NGK on the top pair and oem on the bottom. I'll give it a, try with mopar sensors.

salad

NTK is the OEM supplier

askingxforxit

^^^ NTK, thats what I meant. Got them from napa a couple years ago.

I figured those were bad and replaced with the bosch. When that didn't work I replaced the lowers with bosch. Def going to get oem a try before forking out $1200 for new pre cats

salad

Did you check your manifold bolts yet? Will cause vacuum leak, rough running, lean, and raw exhaust to escape

askingxforxit

I was able to check the bolts I can access from the top and they were tight. I'll check the others tomorrow

OEJ

Completely over kill and not even close to being nesessary. you don't need the precats. so it would be rediculous to pay 2400 for something that is not needed and chokes your exhaust down.

forget the the precat bs. my o2 was so rusted into the stock down pipe. so i bought a walker down pipe with out the precat. it was like 40 bucks at napa. if you have to replace the main cat i would just get a high flow from performance-curve.com I replace my hole exhaust for 180. bucks except for the header.all from napa and perf.curve.

i only paid 40 bucks for the cat and that was 2.5 years ago and still goin strong even for NJ strict emission laws. the precat was more of a sound ballancing fix more than anything else. your mpg and overall running condition will improve greatly with a free flowing exhaust. with the right turbo muffler; it will still be quiet if thats what ur worried about.

The only things i would buy from the dealer are electricall components anything else aftermarket is fine.

askingxforxit

if anything is illegal for sale or use in california the parts stores won't sell or order. I've already got the performance-curve magnaflow exhaust and plan on getting the matching main cat as well. I think I'm going to have to do some "custom" work on this one.