Results of the Ca smog test. from my jeep

[Chris142]

I bought this Wrangler brand new in june 02. Infact it was stil on the top row of the truck when I first saw it.

It still has the original 4.0 Jeep engine and Original Cats . I did replace the O2 sensors with NTK ones about 3 yrs ago. Has 3.73 gears and a 5 speed, 137,373 miles.

The top line on the report says "High emitter Profile".

idle rpm 734
co2-14.7
O2-0.4
HC-3(max - 100)
CO%-0.00(max-1.00)

2611rpm
CO2-15.0
O2-0.0
HC-12(max 170)
CO%0.04(max 1.00)

It passed easily.

I know that HC is unburned fuel usually from a missfire. Looks like my Autolite plugs are working well.

 

[MetalSlug]

I think these 4.0L is alway gonna be high in emission, I read some where that reason they stop making 4.0L cause it cause high emission.

 

[addyguy]

What do people expect? It's a 1960's design!

Yeah, it's got FI..etc...but the basic 'design' is still not an effecient one.

But that shouldn't matter in a Jeep....but of course it does these days, so now we have a high-strung, overly complicated DOHC V-6 in a vehicle that DOES NOT NEED ONE...

Sorry, rant over.....

 

[JHZR2]

Originally Posted By: MetalSlug
I think these 4.0L is alway gonna be high in emission, I read some where that reason they stop making 4.0L cause it cause high emission.


And why are you calling this high emission???!?

Interesting that no NOx is reported in CA.

The only high emissions is all the CO2 coming from this thing because it isnt very efficient and thus an enemy of CAFE. Doesnt look like it is an enemy of CARB in any way...

 

[MetalSlug]

Originally Posted By: JHZR2
Originally Posted By: MetalSlug
I think these 4.0L is alway gonna be high in emission, I read some where that reason they stop making 4.0L cause it cause high emission.


And why are you calling this high emission???!?

Interesting that no NOx is reported in CA.

The only high emissions is all the CO2 coming from this thing because it isnt very efficient and thus an enemy of CAFE. Doesnt look like it is an enemy of CARB in any way...


no no, what I mean is not in a bad way, what I mean is, its normal for these 4.0L old tractor engine have higher # then other car.

 

[JHZR2]

...but Im not seeing that from the results.

 

[L_Sludger]

Originally Posted By: JHZR2
...but Im not seeing that from the results.
He might be referring to the "high emitter profile" note cited in the original post from the DMV. Chris142's 4.0 may have immaculate combustion but other 4.0s may not be in as good a condition.

 

[Chris142]

Originally Posted By: L_Sludger
Originally Posted By: JHZR2
...but Im not seeing that from the results.
He might be referring to the "high emitter profile" note cited in the original post from the DMV. Chris142's 4.0 may have immaculate combustion but other 4.0s may not be in as good a condition.
ya there's bunches of threads on the jeep boards from ppl that let the original plugs go 100k or more when jeep recommends replacement at 30k. it uses a waste spark system and the plugs are very worn by 20k on them. a new set improves the idle smoothness immediately.

 

[SLCraig]

Looks great.
I have never had a car that was even remotely close to failing emission tests. Even if they are an oil burner.
Seems like it's pretty hard to fail, TBH.

 

[Scott_Tucker]

Originally Posted By: JHZR2
Originally Posted By: MetalSlug
I think these 4.0L is alway gonna be high in emission, I read some where that reason they stop making 4.0L cause it cause high emission.


And why are you calling this high emission???!?

Interesting that no NOx is reported in CA.

The only high emissions is all the CO2 coming from this thing because it isnt very efficient and thus an enemy of CAFE. Doesnt look like it is an enemy of CARB in any way...


Since this vehicle is 4wd, they only do a two-speed idle test. They hold it at 2500 rpm for 30 seconds and measure exhaust gases. The they do it at idle. NOx will not show up since the engine is not under any load.

 

[Scott_Tucker]

Originally Posted By: SLCraig
Looks great.
I have never had a car that was even remotely close to failing emission tests. Even if they are an oil burner.
Seems like it's pretty hard to fail, TBH.


I've been working with emissions testing for years. I have never seen an oil burner increase HC emissions unless it was fouling plugs bad enough to cause a misfire. It could have near perfect emissions and still be chuffing smoke.

 

[mechtech2]

This is a singular tribute to the cats.

 

[Chris142]

Originally Posted By: Scott_Tucker


Since this vehicle is 4wd, they only do a two-speed idle test. They hold it at 2500 rpm for 30 seconds and measure exhaust gases. The they do it at idle. NOx will not show up since the engine is not under any load.
I live in an area that only does the hold and rev and not the advanced roller test. My Jeep is not full time 4wd so it can do the advanced roller test easily.

 

[MetalSlug]

2 years ago when I take my camaro ( all emission stuff is off the car, no cat, running off road header with full exhault system, smog pump is off, pretty much all emission stuff is got strip off the car, no rear o2 sensor.. ) to dallas for visit a friend. He is the manager at the inspect station, slow friday afternoon( shop close ) we bore and end up take my camaro in for fun smog test, he knew my camaro really well and knew all emission stuff is off. but we did this for fun. I fail almost every single test, it was a good afternoon. If I ever going back to live in dallas, I will sell my camaro before moving back

.

 

[JHZR2]

Originally Posted By: Scott_Tucker
Originally Posted By: JHZR2
Originally Posted By: MetalSlug
I think these 4.0L is alway gonna be high in emission, I read some where that reason they stop making 4.0L cause it cause high emission.


And why are you calling this high emission???!?

Interesting that no NOx is reported in CA.

The only high emissions is all the CO2 coming from this thing because it isnt very efficient and thus an enemy of CAFE. Doesnt look like it is an enemy of CARB in any way...


Since this vehicle is 4wd, they only do a two-speed idle test. They hold it at 2500 rpm for 30 seconds and measure exhaust gases. The they do it at idle. NOx will not show up since the engine is not under any load.


In NJ they sniff non-OBD II cars, and my 91 BMW reports NOx at idle. They used to throw our cars on a dyno, but now they just sniff at idle.

 

[Jarlaxle]

Originally Posted By: Scott_Tucker
Originally Posted By: SLCraig
Looks great.
I have never had a car that was even remotely close to failing emission tests. Even if they are an oil burner.
Seems like it's pretty hard to fail, TBH.


I've been working with emissions testing for years. I have never seen an oil burner increase HC emissions unless it was fouling plugs bad enough to cause a misfire. It could have near perfect emissions and still be chuffing smoke.


I have never seen an oil burner NOT have elevated HC emissions!