Mechanics

VALVE TRAIN QUESTION

2007 Chevrolet Impala • 156,000 miles

I'm curious is it possible to misalighn a pedestal mounted rocker arm? My car isn't breathing right at all. And I have a pretty pronounced valve train noise from a lot of my rockers. If I pull the covers again what should I look for? On cold starts the valve train is noisy and exhaust is a loud puffing noise, no miss just noisy and a major hesitation/lack of power.

This started after doing a lower intake gasket.

Ps there's no coolant that goes through the intake manifolds

Any testing tips would be great instead of saying go to a mechanic. I'm here cause I would Love to fix it on my own over paying a 100 dollar diagnosis (which I've done 2 times to hear them say "we don't know!") Its not worth it.
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Pos07impala
April 14, 2012.




What motor?

Tiny
Fixitmr
Apr 14, 2012.
3.5 v6 flex

Tiny
Pos07impala
Apr 14, 2012.
You did the gaskets yourself?

Tiny
Fixitmr
Apr 14, 2012.
Yea it wasn't too difficult, I had to fix a crossover leak and I went ahead to replace the manifold gasket, just for the sake of been in that far. The car took a couple tries to start then it started up and was making noise, I think it was the lifters but I'm not sure. Right now it just seems like I have some excessive clearances in the valve train. I checked pushrods and only one had some stress marks and it was very slightly bent, could only fit a post it note under it on a level surface

Tiny
Pos07impala
Apr 14, 2012.
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Tiny
Fixitmr
Apr 14, 2012.
Yep. And do you have any insight?

Tiny
Pos07impala
Apr 14, 2012.
Not at this time. Will keep in mind and see what pops.

Tiny
Fixitmr
Apr 14, 2012.
Alright. Basically I was leaning towards a running compression test, a cylinder Leakdown, or get a dial indicator and measure cam lobe lift and compare it to stock height. Sound like I'm on the right track?

Tiny
Pos07impala
Apr 14, 2012.
Sure, doing anything positive increases the chances of finding the issue.

Tiny
Fixitmr
Apr 15, 2012.

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