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Smog Failed....another thread

cracker

NAXJA Forum User
Location
La Mierda
Well, I barely failed smog in the MJ.....

New engine, very healthy cat (only put on for smog checks), Carb legal air intake.

Some odd numbers are listed on the report as well....seams to be running lean

Other than throwing money at it I don't have, anything stand out?

SMOGRESULTS.jpg
 
definitely looks lean-- apparently only failing at idle, though. I'd look for a source of un-regulated air intake at idle. Possibly a leaking EGR valve that works correctly with RPM.
 
Look for a vacume leak and test your O2, MAP sensor, and coolant temp sensor. Any of those out of spec can cause it to run lean. You can find out how to test each of those with a multimeter by searching.
 
- Check for vacuum leaks.
- Dismount and clean EGR, reseal (I like to use a smear of RTV copper on both sides of that gasket when I put it in - helps with longevity. Screws are threaded 5/16"-18 if you want go with something else, I find hex socket heads easier than the OEM Torx button heads.)
- Run injector cleaner through it anyhow - or acetone (half-pint to the half-tank.) Deposits can collect on the injector nose and diminish fuel spray.
- Look up how I've said to blow carbon out of your chambers, and follow. You can get carbon deposits retaining heat, which will mimic the effects of running slightly lean - and you're either pulling the head off to clean them out (yech!) or looking for another way, I've given you another way that typically takes less than an hour and costs about ten bucks (or less.)
 
Talk about barely. Did you drive hard before you took it to get tested. If not, try manually shifting the auto so you can get it to hold revs in the 4K area, then take it to get tested.
 
- Check for vacuum leaks.
- Dismount and clean EGR, reseal (I like to use a smear of RTV copper on both sides of that gasket when I put it in - helps with longevity. Screws are threaded 5/16"-18 if you want go with something else, I find hex socket heads easier than the OEM Torx button heads.)
- Run injector cleaner through it anyhow - or acetone (half-pint to the half-tank.) Deposits can collect on the injector nose and diminish fuel spray.
- Look up how I've said to blow carbon out of your chambers, and follow. You can get carbon deposits retaining heat, which will mimic the effects of running slightly lean - and you're either pulling the head off to clean them out (yech!) or looking for another way, I've given you another way that typically takes less than an hour and costs about ten bucks (or less.)


Thanks John.

I am checking it out.

BTW, it is a new motor.
 
I pulled it out from the back this morning to start working on it in preparation of my next smog and discovered the air intake had slightly popped off the throttle body. I opened it up and discovered why.....no air could get through the filter. :/

2012-06-24_10-20-02_238.jpg


Here is the CARB legal air intake. This thing has to be the biggest pile of crap ever made then they chrome it. :jackoff:

2011-09-05_13-31-09_520.jpg


This is where the air (and dirt) was sneaking in :rolleyes:

2012-06-24_10-45-50_0.jpg


The air filter only has about 700 miles on it but one trip to JV and two trips to Big Bear. I had no idea it would clog up this bad so quick so I guess I will have to clean it often :/

I am assuming this would probably not help my smog cause.

How much effect would this have on my Smog results? It would then be getting (colder) air now though the cowl as opposed to directly from the throttle body.
 
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I have the same intake. Failed smog due to lean condition. Swapped back to factory intake passed with flying colors...
 
I have the same intake. Failed smog due to lean condition. Swapped back to factory intake passed with flying colors...

I wish I could....I don't have room now with the coilovers :(
 
I wish I could....I don't have room now with the coilovers :(

You figure it out post up so I know what to do....

I tried everything I could think of before swapping to the stock system.

Good luck....
 
So I cleaned the air filter, bought/installed a new 02 sensor, checked for vacuum leaks carefully with carb cleaner, checked the EGR valve and it stalls me out as it is supposed to, found two pin hole leaks pumping exhause out on my downpipe and welded those up. I also checked my flange at the cat and it appears to be sealed ok.

I will try to smog it first thing tomorrow morning. Keep your fingers crossed.....
 
:party:

It appears that it was the 02 sensor that made the world of difference.

scan0006.jpg
 
Glad you got it handled. Now I know some things I need to double check on mine before I go thru the smog crap again.
 
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