XJ2Door

Hello all a little background info.
1993

2.5L manual ax5 231 transfer

It failed the emission test High CO and NOX, so far I have replace:

Plugs, wires, cap, rotor, O2 sensor, All vacuum lines running into the TBI, I have ran one tank of gas through it with gumout mixed in. I found out about seafoam after used the gumout and have a tank with seafoam in it now.

I was thinking also TPS and MAP Sensors and last resort the CAT.

My question is if any of the sensor are bad shouldn't I have a check engine light on? It does turn on before I start then off once it has started, so I know it does light up.

Any help is greatly appreciated, I have been trying to find an answer and fix.

Tkitt21

best way to use seafoam is to undo the line on the brake booster and let it suck it in the intake untill it stalls then let it sit for bout 10min and start it up and watch the smoke fly :P it cleans all the gunk on the inside of the motor up

XJ2Door

Ok thanks I will try that tomorrow.

caged

high co and nox = cat

XJ2Door

That is what I was afraid of. So should I still replace the other Sensors or leave them be?

caged

leave em.

maybe spray the o2 sensor with some brake or carb cleaner tho.

and don't use that guarantee to pass crap. it'll make you fail. and use regular fuel, and keep the engine running when you get to the test center. get it hot first too.


i've had good luck with the cheap flowmaster cats from partsource.

XJ2Door

Thanks, the O2 is brand new I replaced it due to low MPG. I found this one at AutoZone http://www.autozone.com/R,496610/veh...ductDetail.htm

Do you think it will work or does it need to be a direct fit.

That is funny you mention the GTP crap, while in autozone last night a customer overheard the conversation and recommend it while the manager said the same thing you did. He gave me the seafoam to put in the gas tank and I am heading back to buy some to run in the vacuum line.

caged

yup, that's the one i meant. not flowmaster. those ones work great. and they're cheap.

just make sure you run it till it's hot for a bit to burn off any new oil/coating from inside the cat.

you should pass no problem.

XJ2Door

Thanks for all the info, I will pick one up today and try again. I get one free retest Here goes nothing.

OverlandZJ

I also failed emissions last Dec for high NOX, cat was my issue as well.

Replacing also fixed my loss of MPG.

xj4fun

X2 - Not what you want to hear, but high probability of being the root cause.

smtippin

[quote=XJ2Door;140003]Thanks, the O2 is brand new I replaced it due to low MPG. I found this one at AutoZone http://www.autozone.com/R,496610/veh...ductDetail.htm

quote]

Put your last 8 from your VIN in the box on the bottom left of this link and check for recalls. I don't know about the 93s, but my 96 had a CAT recall and they replaced it for FREE.

hope you get lucky,
s

XJ2Door

Thanks for all the input It PASSED with almost no emissions. New Cat did the trick, although it was a pain in the butt to do!!

Thanks again!

XJ-Roz

What link? I'm not required to pass emissions, but my exhaust sometimes stinks. I'm curious if mine will fall under this recall.

smtippin

Oh Sorry bro. The link is: http://www.jeep.com/en/owners. Just drop your last 8 from your VIn in the bar on the bottom left hand corner of the page and see what recalls are open, if any. I've done a bit of research and I think the CAT recall was for 96-97 XJ's, but it doesn't hurt to check.

I don't have to get emissions tests here in Wyo either, but my CAT was rattling like I had a marble fetish (which I kinda do, but I don't stick them in the underside of the Jeep...that's for sure).

Good Luck,
s