NOX of luck

[chast]

My daughters 1995 Jeep Cherokee Country came back with a failing grade from emissions.

Emissions for NOX were 3.32 (3.0 allowed) ...close
Equipment inspection came back with EVAP COMPONENTS - Hoses FAILED

The helpful folks at emissions... (We know whats wrong but can't tell you because someone might sue us if were wrong ...so lets play twenty questions) said it has something to do with faulty or leaking hoses..perhaps from the charcoal canister. They even provided an illustration of (looks like fred flinstones car) a oversimplified EVAP System.

My initial thought (after I check all the hose connections) is the egr valve.

Any comments or suggestions will be appreciated...ask any teenager who has their dad working on their ride.

Thanks...
chas.

[Kings-x59]

The catalytic converter is the component that reduces NOX. It may be partially plugged which points to some other problem, but I gather your service engine light is not on, which it would be if your EGR had failed. There are fuel additives that are purported to clean the catalytic converter, though I haven't tried one yet. The fortunate thing is that the converters aren't near as expensive as when they first came out. Haven't had to replace the converter on my '96 cherokee yet (152K miles), but did replace the converter on my van for a little over a hundred bucks.

[AlohaBra]

Originally Posted by chast

My daughters 1995 Jeep Cherokee Country came back with a failing grade from emissions.

Emissions for NOX were 3.32 (3.0 allowed) ...close
Equipment inspection came back with EVAP COMPONENTS - Hoses FAILED

The helpful folks at emissions... (We know whats wrong but can't tell you because someone might sue us if were wrong ...so lets play twenty questions) said it has something to do with faulty or leaking hoses..perhaps from the charcoal canister. They even provided an illustration of (looks like fred flinstones car) a oversimplified EVAP System.

My initial thought (after I check all the hose connections) is the egr valve.

Any comments or suggestions will be appreciated...ask any teenager who has their dad working on their ride.

Thanks...
chas.

You have two different things.
for NOX...change the plugs and drive the thing on the freeway for at least 15 minutes and keep it hot before testing.... 3.32 instead of 3.0 is not that much off. Leaking hose can contribute to this.

fix the EVAP hoses...search the web for "jeep cherokee evaporative emission system"...

Don't bother with the EGR yet.

What state are you in? Our numbers for NOX are different (CA) and our cars are tested at 15mph and 25mph while running on a dyno.