Just barely failed emission test

[SHO_91]

Ok guys, here's the deal:
Just got back from the vehicle emission testing facility in Phoenix, AZ. Here are the results:

Test .......... Applicable standard .......... My results

HC g/mi .......... 1.00 .......... 0.56
CO g/mi .......... 12.00 .......... 8.12
NOx g/mi .......... 2.50 .......... 2.51 -> FAIL

All other (equipment) tests: PASS
Now to my question(s):

I've been running mid-grade (89 octane) gas, as of recently. Seems to run fine. Would a switch to premium remedy that 1/100 NOx over the limit?

The y-pipe w/ high-flow cats is fairly new. I verified this when I changed my con-rod bearings. The O2s may have 40K on them.

I don't think there's a (major) vacuum leak. I just recently re-did all the couplers on the intake (w/ new clamps). Checked the vacuum lines. They all look good and aren't brittle (checked them last time I had the intake off to replace plugs - Autolite dbl plats - and plug wires - El Cheapo, but they work a lot better than my old Delco wires).

Tried to find that SPOUT plug, to no avail. But I think I found that other one by the coil pack, that's supposed to retard timing by 3 deg overall. I'd like to stay away from that 'Sure emissions pass' stuff, I heard bad things about it.

So, anyone of the tried and true magicians here has a solution, preferably the
ones familiar with AZ testing procedures?

So, finally: On the back of the form with the test results, there is a space for the service technician to sign off on the repairs that have been done to remedy the situation. Do I HAVE to bring it to a shop?? I don't know of any that are familiar with the Yamaha...?

Sorry for the long post...

 

[SHOGUN88]

I just pulled the spout near the fire wall when I got it done a week ago. It took me a few minutes to find it, believe me its there. I most likely would have passed but I didnt feel like dealing with them more than once and giving them another $50.

 

[LJRuddy]

Drive the **** out of your SHO before you take the test. Try to get your cats as hot as possible.

 

[FrakensteinSHO]

Pshh, get alot of that HEET stuff and pour it on in the tank. Thats how my uncle passes his tests in NJ.

 

[shoson]

Pull the SPOUT. First time it's a little difficult to find. It's a grey plug in the electrical harness back by the firewall near the cid sensor. There's another black plug you'll find first but that's not it, go further down. I don't have a pic of it but sure you could find one if you did a search. The plug you mention by the coil pack is not te spout, nor I believe it will retard the timing. On the re-inspect I would just say you cleaned the egr and intake yourself on that form, and with the spout pulled you will pass,

 

[hawkeye18]

Drive **** out of it, pull SPOUT connector. First part is optional, but always recommended.

</thread>

 

[Kens1992mtxSHO]

+ 4 on the spout connector and + 3 on driving the **** out of it

 

[zak]

Mine was just like yours. I had to pull the SPOUT as well as use premium fuel. Curious if you are using the Magnaflow converters, once I made the dwitch to those my NOx levels started to climb . . . zak

 

[projectSHO89]

Elevated NOx readings aren't caused or affected by converters. They're caused by combustion chamber temps that are too high. On EGR-equipped vehicles, the EGR gasses that are added force combustion temps down and lower NOx readings. Since your car (MTX) doesn't have an EGR system, you have to approach the problem from a different anle.

Simplest is to pull the SPOUT #1 plug (the one by the cam sensor). The engine will run like a pig, but the emissions will be lowered so you can pass the e-test. You can also pull the SPOUT #2 plug (the one by the coil) which will pull 3 degrees of timing globally (contrary to to the WRONG info above).

For more info on the SPOUT plugs, see this reference thread: http://www.shoforum.com/showthread.php?t=56278

Steve