Not another emissions thread! Ugh. (1 Viewer)

Chad717

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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.
 
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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.
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.
 

Chad717

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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.
 

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