Not another emissions thread! Ugh. (1 Viewer)

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So I started walking back through the AI tests cause I had some time and when I got to the Deceleration Fuel Cut system, that failed. I pinched off the vacuum hose to the vacuum switch and ran it up to 2000 rpm, no air came out of the ABV. The engine didn't even misfire like it said it would. So I'm wondering if I need a new vacuum switch or VSV 2.
 
So I started walking back through the AI tests cause I had some time and when I got to the Deceleration Fuel Cut system, that failed. I pinched off the vacuum hose to the vacuum switch and ran it up to 2000 rpm, no air came out of the ABV. The engine didn't even misfire like it said it would. So I'm wondering if I need a new vacuum switch or VSV 2.
You might be on to something. I recall swapping an old ABV into the truck and having fuel delivery issues on top of the emissions problems. I changed the fuel cut solenoid and solved the problem. That’s when I decided to check the continuity of the VSVs and found the bad one. I performed the “hack” I was mentioning and passed emissions. Definitely double check all the electronics. Could be your problem.
 
Just wanted to post an update for you all. So I dove back in after a long hiatus and I went ahead and put a smaller jet in the primary. 1.36 I think. I drove it around a bit to get it warmed up and I went and passed with flying colors. I wish I had just done this earlier! The truck runs good like this as well. Although, I am thinking it’s probably better to go back to stock to keep from running to lean. Our emissions are good for 5 years.
 
To answer your question about other people in the Denver area passing - I did not have to change my jets, but like cps432 i had to work hard to get it to pass and finally did it (but not like cps432 😊). Feels good, right? Anyway, I can’t believe you have 19in of vacuum. I need to fix mine - it’s so low comparatively. @cps432 what is your vacuum? I’m pretty sure my leak is that damn intake MHP never got flat. Years ago I picked up another one to replace. Need to do that!
 
To answer your question about other people in the Denver area passing - I did not have to change my jets, but like cps432 i had to work hard to get it to pass and finally did it (but not like cps432 😊). Feels good, right? Anyway, I can’t believe you have 19in of vacuum. I need to fix mine - it’s so low comparatively. @cps432 what is your vacuum? I’m pretty sure my leak is that damn intake MHP never got flat. Years ago I picked up another one to replace. Need to do that!
I think the last time I checked I was pulling around 14in. But that’s been a while since I checked. I’m due for emissions very soon. Not looking forward to it...
 
@Infinity00 just for the sake of accuracy, my vacuum is 18. I went back and looked at my first post and I must have mistyped 19 cause I said 18 in the line before it. Still very happy with that number! Fresh engines are great! So excited to have it past emissions. Five years of not having to worry about it. I am even thinking about maybe desmogging it for the five years, but I have a lot of other things I want to get done first. I hope in five years I am living in a non emissions county
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Same as @cps432!
You may have noticed after I got mine passing, I got the 5 year plates, to avoid it for awhile! I just finished looking at @Chad717 write up and MHP receipt and it doesn’t look like he got his intake planed by them. I had my engine work done by them as well but asked them to plane my intake m/exhaust together - twice and they didn’t get it right. And he’s getting 18

Sorry for the hijack Chad!
 
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Like others before me have said, desmogging it was like night and day in how mine ran and it’s hard for me to believe that it could be polluting more (it’d be fun to see what the numbers are, $25 to find out if they’d put it thru)
 
I like the hijack! The more talk the more info. They did not plane my intake. When I got the truck the PO had put on headers and a brand new intake, so it was in pretty good shape. So you did the desmog @Infinity00? I have a couple extra smog pumps, so I was gonna debate one, but then what do I do with the CAT? Will the cat be ok without the air from the smog pump going through it?
 
I doubt it will be okay. I read up on it at the time but I don’t remember the consensus. But likely not good. I left mine in as it can continue to help remove some pollution I’m guessing. Some people suggest removing, others leaving in IiRC. Other people probably know more on the subject then me. The way I thought about it was it might do some good to remove pollutants and if it dies by the time my next emissions comes up I’m pretty sure I needed a new one anyway, and the aftermarket ones aren’t that expensive.
 

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