I think I may have fixed it! Drove it for about a half hour and light didn't come on, which was longer than the last time the light came on. (update: still hasn't come on after a few more days of driving and gas mileage seems improved so definitely seems fixed) It was just bothering me that I couldn't find a leak last time so I tried the same method before, spraying every connection with starter fluid and this time it worked. However, the difference this time was I just drove home. Last time it was on a cold start. I think that was actually the part that mattered! I'll explain why I think that in a second...
I recall when installing the intake kit that the hose that sits on the right was a pretty tight fit.
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So when I sprayed the connections of the hose, I pulled it off with the intent to check for a tear or something, but it was so loose! It was a little hot, maybe shouldn't have done that - but it makes sense since stuff expands when heated. It was loose enough that I'm 90% sure that this was the issue, I don't think I've driven enough to determine that yet though. However, I cannot overstate how loose it was when the engine was warmed up. What doesn't make sense to me was why it was fine for a bit (50 miles), and then suddenly became more loose. Maybe the material stretched? I noticed when the hose was warm it was significantly more flexible.
The (potential) fix? Just a little hose clamp. You can tell I sprayed where the hose connects quite a bit because I just couldn't believe I thought i found the issue lol.
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So I have some questions now, what does this hose connect to? Does my thinking make sense? I guess I just want an explanation for peace of mind. Does anyone know how long/how lean it has to run before the check engine comes on? I feel like this may be a super heavy math question.
And lastly, I noticed the other intake hose is connected SIDEWAYS and is somehow NOT leaking. The way it sits in there just really bothers me. Looks like it's fine considering all the dirt/wear looks very even but I figured I'd share.
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