Chevrolet: 2002 Venture Valve Chatter, oil pressure gauge, valve lifter

Question
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Followup To
Question -
About 6 weeks ago, my 2002 Chevy Venture minivan with the 3.1L 6 cylinder engine started chattering on start.  Someone told me to try a higher octane gas.  It quit.  It started again two weeks later, chattering all the time.  That went on for about a week, then quit.  It started again Monday, so I took it to the mechanic yesterday, and he said it might be a worn rocker arm.  This morning, it is quiet as a kitten.
A worn rocker arm would rattle all the time, right?  What else might it be?
I only have 69,000 miles on it, have the oil changed every 4,000 miles and it uses no oil.

Thanks,
Jennifer
Answer -
Hi Jennifer, Your right, a worn rocker arm would not go away. It is very hard to diagnose a engine noise without actully hearing the engine. It is probely a sticky valve lifter (this is common for this engine). You should get several opinions before you start spending money for things thats not broken. I hope this helps you. Regards, Keith.
ps. a worn rocker would not stop it from starting.

I appreciate you response.  What repair would have to be made on a sticky valve lifter?  Someone also mentioned to me the oil pump.  I don't have an oil pressure gauge, but no lights have come on.  Is that a possibility?

Thanks,
Jennifer

Answer
Hi Jennifer, A sticky lifter would have to be replaced to be fixed (its an expensive job so you need to be sure its the problem). The oil pump is a possibilty, but not likely. Also you could have the engine checked for sludge buildup wich may be restricting oil ports causing a chatter, you can have it cleaned with an engine flush by a mechanic. I hope this helps you, if you need more info just let me know. Regards, Keith.