3rd gear bogging

[Zach079xxx]

Now that you say that, about the gas cap... The man I bought the truck from painted the entire truck and while doing so painted the gas cap, when I would have a full tank of gas it would leak out the back side like pyshically inside the wheel well, but coming from the cap. I bought a new acdelco cap and when I get gas at a gas station, I'll loosen the cap and psshhhhhhh for 4-5 seconds the pressure is released. Dang.... If it weren't after midnight I'd go run it with the cap off and see if that changes it. It's so weird thigh because I've had the gas cap for months & the truck ran amazing after the rebuild then surprise the unknown happens. Hey thanks guys, I appreciate all the help. Going to update tomorrow

Should I have a vented cap?

[rich weyand]

It got cold enough for the gas to shrink enough to create enough vacuum....

Like I said, just run a 1/16th-inch drill through the center of the cap. That's all I did. On both caps. Five years ago now. No problems.

[rich weyand]

Originally Posted by SkinnyG

Going out on a limb - try a run with the gas cap off. Perhaps (long shot), that the tank isn't venting enough to keep up with the fuel needed, creating a partial vacuum. A cheap test anyway, on your way to buy a timing light (grin).

Hey, SkinnyG: Nice catch! Sounds like you got it. Forgot all about that. It's been five years since I vented my caps.

[Zach079xxx]

I'm going to test this tomorrow. Glad you guys pointed this out. Wish I had the joy of 2 tanks. My engine sure sucks the gas, sometimes I swear I can see the needle moving down. BUT I enjoy my square more than my 08 Cadillac SRX. Love them both but there's something about a square!

Still can't wrap my head around why it only acts up once third gear hits

[rich weyand]

Originally Posted by Zach079xxx

I'm going to test this tomorrow. Glad you guys pointed this out. Wish I had the joy of 2 tanks. My engine sure sucks the gas, sometimes I swear I can see the needle moving down. BUT I enjoy my square more than my 08 Cadillac SRX. Love them both but there's something about a square!

Still can't wrap my head around why it only acts up once third gear hits

Because 1) you are using more gas and 2) the rpms went down, which reduces the amount of strokes per minute the mechanical fuel pump takes.

And I agree with you: Ain't nothin' like a squarebody.

[Zach079xxx]

Will update in the morning good sir, thanks for the tips.

[Zach079xxx]

Thank you BOTH for mentioning the gas cap! It was acting up with 3/4 tank of gas, took the cap off and drove and it ran fine! I put a vent hole in the cap so we'll see how it goes. I can't thank you guys enough for the help. Finally I can enjoy my truck as much as I'd like to! Hope this fixes it permanently. Again, kudos guys.

[SkinnyG]