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Old 01-29-2013, 03:05 PM
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cobalt327 cobalt327 is offline
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Quote:
Originally Posted by Chevyman87 View Post
I adjusted the valves and still nothing now it makes a weird noise when driving the truck. I pulled the spark plugs and they seemed fine. A buddy of mine helped me and we pulled the valve cover back off and turned the motor and no stuck valves. I have a recording of the noise but since I'm on my iPhone I don't think I can post I am stumped. I haven't experienced any loss of power just a shake while idling and a weird noise while driving.
Could be a vacuum leak. Is the sound you're hearing a whistle or sucking sound like air rushing through a small opening?

Check the vacuum lines- there's one that runs to the transmission (to the modulator valve). You can remove the vacuum lines from the vacuum ports of the carb and intake manifold one at a time and plug off the vacuum port w/your finger to see if the idle smooths out. If not, reattach it and go to the next vacuum port and do the same thing. Keep on until you either find one that makes the idle better, or you run out of vacuum ports.
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