Almost Failed Emissions...

[xploded]

Had my first emissions test since building the new engine in the explorer. The test is the 2-speed idle kind. One test at idle (792rpm), and one was at 2707rpm. I had high Hydrocarbons across the board. 114 out of 220 at high rpm, and 220 out of 220 at idle. That's right, I hit the max dead on. My CO emissions seemed perhaps high as well. .73 out of 1.2 at high rpm, and .35 out of 1.2 at idle.

So, the thing is, next year I don't want to have 221 hydrocarbons and fail. My question here, is what should I look at to lower these numbers.

My truck is a N/A OHV with the 422, stage 3 heads, headers, and all the goodies. My catalytic converter is the stock one that came in it in 1993. (That worries me a little.)

I have read all the archives in RPS, Pro 4.0, and Explorer Forum, and I'm ready for some better info.

Has anyone else out there with these same mods had trouble with emissions? If you didn't, what were your numbers?

I know that the cam will increase emissions due to the overlap. But, what else will increase it like this. Perhaps, my cat, or a rich/lean condition? Could my old O2 sensors have anything to do with it? The chip?

 

[boominXplorer]

cat deffiniatally. If you have access to a nice scan tool that can check O2 sensors to read the voltage that would give you an idea. Now if you had O2's after the cat (didn't happen till 96 I think) then you could compare B&A the cat.


I WANT TO SEE PICS OF YOUR TRUCK!!!!

 

[410Fortune]

next year run a can of sure pass just before the test, you will pass.

Get a new single cat, I ran a 2.5" in and 2.5" out with 2.25" pipe in front (from the headers) and 2.5" out to the muffler. Good setup for the OHV

 

[xploded]

thanks for the quick response guys. It seems that 90% of the guys on the threads out there agree that it is the old cat. I think I'll pick up one of those single high flow cats and have an exhaust shop weld it in place of the old junker.

Boomin: I just added my website to my signature. It has some older pics of my truck there. No really good quality pics, but you'll get the idea.

 

[410Fortune]

Also I dont think your numbers should be that high, even with the cam, etc you should be under the limits more, are your 02 sensors, MAS everything working correctly?
But

Then again I have heard the 422 grind cam will not pass CA emissions, so maybe I am wrong.