Had a tough time getting through emissions this year

[Carl Morris]

In past years I always passed the first time with minimal hassle, but after two years of zero maintenance and running 100% pump gas most of that time, my tuning was off.

On the first attempt I just drive it in and the HC was way high. I dumped in about 3 gallons of E85 and changed the plugs and *almost* passed but still failed the HC by about 2% over. I mistakenly thought I was still too rich and leaned it out some more and HC went way back up due to misfires. Got some graphed data from the second failure that showed me that much of my problem was on deceleration, which helped me adjust the VPC a bit differently than I'd adjusted it for the second attempt.

Fixed my mistakes and finally passed on the 4th attempt but not by much. In a couple more years I'll probably buy some new plug wires to try to reduce misfires to the bare minimum next time I have to do it. It was just weird because I've never had any problems before.

[Wazzelby]

I absolutely hate emmissions tests. I usually dont have too much trouble passing, it's getting them to test my car that's the real PITA. Every year they come up with some new excuse about how my stock bumper isn't stock, or my 17" wheels aren't the "factory size cause mitsubishi didn't make an eclipse with a 17" rim"... Yeah..

[BlueVelocity]

Yep, I had the same issue Carl. From what I understand, they changed the emissions standards about a year ago. It's a little harder to pass now is what the guy at CAC told me.

[Mr. Moose]

What's an emission test? Up here in Larimer County, we don't have no stinkin emissions tests... :)

Hi, Carl :)

[Carl Morris]

All I can tell is that misfires upon letting off were killing me, from the data they provided. By turning up the "Response" on the VPC all the way (provides extra fuel when you hit the gas and pulls more fuel when you let off) it happened less. All these years I assumed if I ever had a problem it would be due to richness when they get into boost, but that wasn't nearly as much of an issue as misfires when letting off the gas.

My guess is that if I had ever gotten around to implementing speed density inside the ECU that I might be able to tune the problem out with enough work. No way I'm going to take on that project just to pass emissions, though. I'll just leave the thing in Wyoming and buy a different daily driver if it comes to that.