Topic: Jeep smells very rich

[JFortner5]

I just bought a TJ a couple days ago.  I didn't notice it until today, but the exhaust smells really rich.  It isn't throwing any codes though.  I was thinking about trying the MAP sensor or o2 sensor, but I was hoping there was a way to better diagnose it.  I can't hear any exhaust leaks, but I can't rule that out for sure.  The Jeep has 150k miles on it.  I know the 2.5L's aren't known for power, but it seems like it might be a little more sluggish than others I have driven. 

I hope this doesn't cost alot...


Thanks for the help,
Joey

[Bounty Hunter]

It's not throwing codes or the CEL isn't illuminated?  I've seen some CEL bulbs removed or the wire to the CEL cut on Jeeps coming from shady car lots.  If you're relying simply on the CEL, I'd have the codes pulled just in case.

Consider disconnecting the battery completely, grounding the pos cable to the neg, and turning the headlights on.  Then hook the battery back up and see if resetting the computer helps.

[sharpxmen]

can also be the catalytic converter

[Jeffy]

Could also be leaking fumes from the tank seal or rubber lines above the tank.

[JFortner5]

Thank you for the responses. 

I think I may have an exhaust leak upstream from the o2 sensor.  I think this because I can smell exhaust fumes while driving down the road.  I know that with the top down that is normal, but I smelled it today with the top up.  It doesn't smell like fumes from the tank, it smells like a 77 Ford LTD. 

My theory is that I have an exhaust leak, which is giving the o2 a false reading causing the computer to dump too much fuel in.  It definitely feels sluggish and has a slight hesitation/bog starting around 2k rpm.  I still have not had a chance to check the plugs, but I the wires and distributor cap look brand new.

Thanks again,
Joey

[sharpxmen]

Thank you for the responses. 

I think I may have an exhaust leak upstream from the o2 sensor.  I think this because I can smell exhaust fumes while driving down the road.  I know that with the top down that is normal, but I smelled it today with the top up.  It doesn't smell like fumes from the tank, it smells like a 77 Ford LTD. 

My theory is that I have an exhaust leak, which is giving the o2 a false reading causing the computer to dump too much fuel in.  It definitely feels sluggish and has a slight hesitation/bog starting around 2k rpm.  I still have not had a chance to check the plugs, but I the wires and distributor cap look brand new.

Thanks again,
Joey

when was the last time the cat was replaced? If it leaks ahead of the cat could mean it is partially plugged. Not saying that's it for sure but you should consider looking into it.

[JFortner5]

As far as I know it is the original.

[jfrabat]

Ma, you re lucky your Jeep smells very rich...  Mine smells INCREDEBLY POOR!!!!     (sorry, uld not help myself!)

If it is really rich as you think it is, the cat would be igniting the fuel, whch would cause it to self detruct, and would take the muffler allong the way because all the little cat parts would get stuck on the muffler (dont ask me how I know that).  I think it's more of a fuel leak somewhere...  Keep in mind that while driving, the air you breath is actually coming from BEHIND the Jeep (as in, where the fuel tank is at), so it's normal for you to smell a fuel leak while driving.

[sharpxmen]

As far as I know it is the original.

what year Jeep and mileage we're talking about?

[JFortner5]

Its a 98 with 150k.

[sharpxmen]

Its a 98 with 150k.

if it's original I would think it should be replaced, but I can't tell you for sure that's the problem.

[JFortner5]

Ok, after paying really close attention to it, it does not smell rich.  I just smells like exhaust that has not passed through the cat, but it is really strong.  It stumbled a little today after work when I first took off, but it never did after the engine warmed up.  I am thinking I have an exhaust leak that is closing up a little after everything warms up.

Could an exhaust leak cause loss of power and not running too great? 

Thanks,
Joey

[Jeffy]

Cat's are only good for about 10 years.  Other guess could be a damaged cat.

[sharpxmen]

Could an exhaust leak cause loss of power and not running too great? 

not really unless it's a significant hole/crack at the header/downpipe before or close to the O2 sensor

[JFortner5]

Im pretty sure thats where it is.