Well, we will know if this stuff worked next week on Friday. I am off work on Friday next week and be able to take it in and get it retested.

 

Well, that stuff I did worked! After replacing the plugs, Air filter, gas cap, and putting in premium and a bottle of G2P, I passed with flying colors!

 

well i have heard that the gas cap is fairly important on fuel injected vehicles. i know my moms car turned on the check engine light when my sister didn't put the gas cap on right. i think not having a gas cap installed or one that is not working correctly could let the engine run rich.

 

Here in NM they check it seperately and mine failed last time. That alone didn't fix the problem, but the other stuff did for sure.

 

but if the gas cap is letting the fumes out instead of having them sucked into the engine and burned then your truck could possibly burn more gas and create more emission.

 

True, which is why they test the cap. I did pass 90 days earlier with the old cap though.

 

you also passed 90 days earlier with all the other old parts also. something must have happened to the gas cap in that time. i think since they tested it and it failed last time it must have been the biggest problem. i am pretty sure fuel injected gas tanks need to be kept under vacuum or pressure while running to keep the emissions down.

 

Oddly enough the thing that failed was the gas cap, and the truck at idle only. Hard to say why it failed at idle but I remember that day it smelled like fuel at idle....don't care really as now I have a pass certificuit in hand and am registering it tomorrow.

 

I asked one of the techs at a local dealership who is factory trained and he said a bad cap fails smog because it lets too many gasoline vapors out of the "system". He said it doesn't make the motor run rich but can turn on a check engine light which MAY make the car fail emissions testing. He told me there is no way it can make a car run rich because the gas tank (other than if it has gas in it and what octane) is not a part of the cycle the computer uses to test and set the timing and rich lean condition. I asked about my truck and he said any one or all the things I did could have effected the reason it failed or passed this time and said after looking at the original cert ONE of the reasons was the gas cap. The truck failed before the guy tested the cap which was the last thing he did on my truck.