O.K. So now I've failed emissions, also

[jeepguzzi]

Just got back from the sniffer. I am hoping you people will be able to help me get the cherokee past the emissions test.Here are the facts:
Standards: HC=600; CO=6.0
test results(1999) HC= 9; CO=0.0
test results(2001) HC=328; CO=7.5
As you can see, I failed with too much Carbon monoxide. What do I adjust to bring this down? Will this adjustment affect the Hydrocarbon levels, and will they go up or down? :confused: :mad:

[Yaz]

i failed that also, i was told that i must have been rich, i dont know for sure though i never tried it again..

[Stuka]

Here is what my '75 cherokee with a T18a and 360 4v got when I smogged it last year. This is with the EGR and air pump hooked up.

Idle:
HC PPM- 0300
CO%- 3.00

2500 RPM:
HC PPM- 0350
CO%- 3.50

This was just bringing it in, without a tune up or anything. Prolly would have been lower with a good tune up. I currently have 160k on the engine, at the time of the test I had about 157k.

To get yours to pass make sure your EGR is opening up and working correctly. Make sure you plugs are good, and that your air pump is pumping air, and you dont have a pluged check valve or anything (check valve goes between the rubber air line and the steel spliter that goes to the exhuast manifold. Make sure your timing is right (although they always mess with it) Get it running pretty lean, if you only get tested at idlle, then you only have to mess with the idle mixture screws. Other wise you may have to mess with the metering rods to get it to run lean at 2500rpm.

Cant think of much other stuff then that.

[andy d]

change the oil, replace or remove the airfilter. sniffer means they aint looking @nox, so get the rig hot. crank up the idle speed to at least 1000rpm. whats the cat like? dope the gas with methanol 12oz per gal. bribery? what kinda mods have you done between tests?

[ironroad29]

3 bottles of gas dri .....former n.c. state inspector ...shhhhh

[jeepguzzi]

I have a new Random Technologies Cat. So I hope that isn't the problem smile.gif I did put in a new edelbrock cam, performer intake (with EGR) and 1405 4 bbl. carb. and Doug Thorley headers (with air tubes installed). :D By gas dry, do you mean HEET?

[ July 09, 2001: Message edited by: jeepguzzi ]

[reddog]

I think that anything with methonol in it will serve the purpose. Sounds like if you lean up the carb via the metering rods as Stuka mentioned. This should bring down both HC and CO.

Kerry

[Dennis]

State of GA standards are much higher!

I am at 3.23% CO and allowable is 1.91%. I am down from 7.09% in March.

I have replaced the EGR, PCV, plugs, wires,cap and rotor, coil, changed the oil, added every guaranteed to pass additive I can find. I have reinstalled all the smog stuff that I can find wrong on the Jeep and have ported the smog pump directly to the cat. (I do not have the divirter valve or the banjo bolts on the manifold.)

I am now wondering if the cat is suspect. Is there any way to tell if the cat isn't doing its job? (Other than clogged)

See my post "leaking transfercase" for what happened today at the test station. Be careful out there!

[jeepguzzi]

Dennis, the emissions should be the same, state to state,(except for California) the difference would be in the year of vehicle. I imagine that the standards were strickter between your 1988 and my 1979. You need to put in the diverter and air tubes, you are doing o.k otherwise, and it gives me hope for the 1985 J10 when I take that in. :(