OAS

Was crawlin around under my '97 Cherokee just to check a few things and noticed........
That the previous owner had nixed the catalitic converter.
(well i had noticed it earlier, but it didnt bother me.)

What does bother me now, is that there is a sensor (oxygen sensor???) that has been wrapped in tape.
It is wrapped up nice and neatly and taped to the floorpan.
(on a bracket that has a blackbox attached.)
Ive been driving this for a month now, and have no idea how long the previous owner had been operating it this way.

What worries me is doesnt this help control the fuel injection?
Would this make the engine run rich? or lean??
Or does it not matter at all???

It seems to run just fine, and fuel milage hasnt suffered at all.
(15mpg in town , 24mpg out on the highway)

This computer controlled stuff gives me the heebiejeebies.
Do i need to get a CC and rehook this stuff up again?
Or is it o.k. without?

Thanks for any info!

JayM

The O2 sensor does provide a feedback loop to the computer that determines how rich/lean the mixture is. You will want to look for an O2 fooler box. Basically the O2 sensor is a vairable resistor, depending on what the sensor is sensing. A feedback voltage will go back to the computer that varies between .1vdc and .5vdc, and the computer will make adjustments in the mixture. A few companies make a fooler kit that allows you to send the correct signal to the comuter reguardless of what the actual exhaust is. This is a requirement if you want to do Hydrogen injection.

For me, this would have been enough not to buythe Jeep. You never know what the guy was doing. As far as buying a Cat, and getting this hooked back up. I woudl do so, but you are goingto need help - if the Previous Owner did install a fooler, you will need to find and remove it. This is one of those computer controlled heebiejeebie things so ask someone with expereince for help, as a mistake could cause you jeep to stop running.

93XJLI

is the sensor attached to that black box? this sensor would be after where the cat would be if it was there correct? if so, that sensor merely tells the computer that the cat is working properly. since youre not getting a CEL, id imagine someone put a resistor in it to fool the computer that its there and functioning correct. its not harming anything, but once you get the time and cash id bring it to an exhaust shop and have em put a new cat in and plug in that sensor.

OAS

I probably will end up putting a new CC on sometime soon.

But what got to me was if i hadn't been crawlin around under there, i would have never noticed!
My son drove it and noticed nothing either.
(he has had a '96 sport for a while)

Doesnt run or idle rough. Accelerates well. (REALLY well actually)
I havent pulled a sparkplug to check, but it doesnt seem to be running rich.
(no black smoke)
There is no black "fooler" box that i can see.
The sensor is wrapped around what appears to be a black plastic hook (bracket?) directly in front of the heat sheilding for the muffler on the underside of the floorpan.
At first it looked like a box, but after removing the tape it's just a bracket.
The end of the sensor is well taped and is taped around the bracket.
Its very neatly done, and has a section of pipe where the CC used to be.

I wouldnt pass by a nice vehicle just cause a CC was missing though.
I had an older Thunderbird a while back that i took all of the emission junk off of.
An '80 with a '84 5.0 h.o. out of a Mustang GT.
But back then things were simpler.
Take off the pump, block off some lines, heck i even had a '66 Shelby 715cfm carb on it. (and dang it did run rich)
But it ran very well.
The CC i could care less about.
I was just concerned about the possibility of this Jeep running too rich, and maybe shortening engine life.

Luckily there is an exhaust shop that is heavy into Jeeps and offroad vehicles nextdoor to where i work.
So i can get this done at a reasonable cost.

Just in case though...........where do you find these "black boxes"?

OAS

Uhhhhh what's a CEL?

epic.jeeper

Check Engine Light