High NOx
#1
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Year: 1990
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High NOx
That time of year for emissions...
HC: PASS 0.82 (Allowable 2.0)
CO: PASS 7.80 (Allowable 20.0)
NOx: FAIL 4.03 (Allowable 4.0)
Here are my thoughts...BG 44K in gas tank (run it through) New airfilter, new fuel filter (these two need to be done anyways- didn't replace them when I replaced plugs/wire/rotor/cap few months ago). Verify TPS is at correct voltage.
Should I remove and clean the EGR valve?
I drove the Jeep for about 25miles on the highway but then I stopped off at home for about 15-20min and then the drive to the emissions was all surface streets for about 15-20min of drive time. I imagine the converter was warmed up enough but next time I won't stop off at him first.
Plugs/Wire/Rotor/Cap was all done about 2 maybe 3 months ago. I kind of want to rule out cooling system (just replaced radiator/tstat/housing/hoses/flush/water pump) same time I did the plugs etc... Replaced it all when I replaced the camshaft.
You guys think doing those things will drop me from a 4.03 to a 4.00 lol
HC: PASS 0.82 (Allowable 2.0)
CO: PASS 7.80 (Allowable 20.0)
NOx: FAIL 4.03 (Allowable 4.0)
Here are my thoughts...BG 44K in gas tank (run it through) New airfilter, new fuel filter (these two need to be done anyways- didn't replace them when I replaced plugs/wire/rotor/cap few months ago). Verify TPS is at correct voltage.
Should I remove and clean the EGR valve?
I drove the Jeep for about 25miles on the highway but then I stopped off at home for about 15-20min and then the drive to the emissions was all surface streets for about 15-20min of drive time. I imagine the converter was warmed up enough but next time I won't stop off at him first.
Plugs/Wire/Rotor/Cap was all done about 2 maybe 3 months ago. I kind of want to rule out cooling system (just replaced radiator/tstat/housing/hoses/flush/water pump) same time I did the plugs etc... Replaced it all when I replaced the camshaft.
You guys think doing those things will drop me from a 4.03 to a 4.00 lol
#3
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#4
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FYI: There's nothing under your username when viewing the site on a smartphone. It isn't a matter of not wanting to look, it isn't there.
I'd clean and check the EGR valve and take a look at the MAP sensor, IIRC yours has one..
I'd clean and check the EGR valve and take a look at the MAP sensor, IIRC yours has one..
#5
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Good point, I just noticed that, my mistake. Thanks for the input, good call on map sensor.
#6
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You can try all those things, and it might help, but you should be prepared to replace your cat. You can get a really nice stainless spun cat from Performance-Curve.com for like $60-70.
#7
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Frickin app.
Can you guys see the stuff in signatures?
Can you guys see the stuff in signatures?
Trending Topics
#9
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#10
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Jakers, I think you need to fill your tank with gas and add a can of 44K to it. Run the Jeep hard all the way to Prescott. Buy me a few micro brews. Refill your gas tank and drive home.
#11
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44k has been ordered, will be delivered this week. Although not sure if I can make the Prescott trip. Might be going to Sedona in a trail run this weekend. Although I just found out my block in the Patriot is warped... No clue how. Dealership is currently trying to get Jeep to replace it. Should be covered under power train warranty but Jeep is requiring all these tests to be done... Arghhh
#13
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#15
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I still do the majority of all my forum stuff on my computer. Heck, even if apps were as complete an experience, phones are just way too small to comfortably do all my writing on. And I can't imagine writing or reading some of my larger write-ups on a phone.
Last edited by mschi772; 02-21-2016 at 07:33 AM.