Hi,
I have a question about my 1995 yj. I had a leak in a vacuum line that plugs into my charcoal canister filter and my fuel pressure regulator. It took me a while to find the leak, and by the time I had found it my Jeep was well on its way to hell. It burns black smoke, bogs out when I accelerate from a stop and almost stalls right out when I am slowing down. It has the nastiest fuel odor and going through the gas faster than I have ever seen it do before.
I have taken it to a small town mechanic and had a diagnosis done on it. The results were a lazy o2 sensor. After changing that, along with my plugs wire and rotor and cap, I still had the same problems. I took it back and the mechanic said "nope its the o2 sensor, maybe you have a defective one." So I changed the sensor again to no avail. Back to the mechanics shop again where he suggests changing my map sensor and an injector cleaning. Guess what, it didn’t do a thing. I have since gave up on the mechanic and his $85.00 o2 sensor diagnosis and now I am here get some free knowledgeable advice.
I have changed the map sensor, o2 sensor, plugs and wires, rotor and cap, fuel, air and oil filters, the fuel pressure regulator and the vacuum tube, I gave the throttle body a good cleaning along with the sensor that plugs into the throttle body (the ISA motor, I think it may be called) according to the mechanic my throttle bodies fine, my ISA motors fine and I have no fuel line leaks, all my filters are new and clean.
I wonder now if I wouldn't benefit from changing my charcoal filter and purge valve? (seeing that the leaking vacuum tube plugs into it) I also wonder if there’s something we hadn't thought of.
I am also wondering if a Cherokee charcoal filter would be compatible with my 2.5 L ?

Thanks

btt

Kay well the only advice I got was "BTT"
What in the world does that mean? British thermal temperature- before the time - bite the tailpipe...what???
Any one else got something a little more useful for me?

TPS or CPS. No codes?

I thought about the TPS and had taken it out and cleaned it off when I cleaned out the TB but I haven't replaced it though. Can a person with little mechanical exeperience change a TPS? I had no trouble yanking it out....
I hadn't thought about the CPS, but I am going to see about that one today. I need an ohmmeter to test that one right?
The only code that comes up, is the code for my O2 sensor (21) If one of those sensors had issues, wouldn't it show up on one of the 3 diagnostics I had done? Am I putting to much stock into these diagnostics?
Thanks

TPS is easy.. CPS.... not so easy. I have never been successfull at replacing the CPS with out pulling the transmission. I had rough idle issues on mine, IAC and TPS went out. Two weeks later I had to replace the CPS. Map is the only part I have not had to replace!

Good news though... CPS and IAC are about 40 bucks each and easy to replace. I hate recommending spending money on parts that "may" fix the problem... but you are throwing a code for an oxygen sensor (assuming you got the right one?...only run bosch with factory wiring connector) and that is not fixing your problem. You could take it to a shop and spend a hundred bucks on diagnostics, or spend a few bucks less and replace some parts.

shit.. just thought of another probable cause.... any air leaks on the throttle body or intake manifold?

YES !!! I do have a leaky manifold gasket. It was next on the list of the 'things to fix' before this vacuum leak from hell happened.
I think I'll replace the gasket, then TPS and IAC and just pray its not the CPS. If that doesn't work I am seriously just gonna say screw it and buy a gas mask.....
Thanks for the ideas
Monique

k dude. just cause you have a 02 sensor code doesnt mean you should replace the 02 sensor. usually they come up as reading a lean mixture. why? because there is usually a vacuum leak. id fix that gasket issue and see how it goes. listen for any other vacuum leaks. if you dont know what they sound like run a propane tank along any areas where vacuum could leak out. if there is a leak the engine will idle smoother or rev up a little as it sucks in the vacuum. and it will go away as you remove the propane.
keep us posted. im curious.
e;)

Thanks for the help with the YJ. I tried all of the suggestions....(minus the CPS) good as they were none of them worked out for me. I have found a great solution to my problem though, I parked the YJ, started to yank the engine and bought a Liberty....POOF fuel smells gone!!!