I have a 2001 chevy astro ls awd van. It has a constant whine, in park, driving, acceleration, and deceleration. Any suggestions?

SOURCE: How do you change sparkplugs on a 2000 Chevy Astro

I always take the tire off and go through the wheel well. The middle one is the toughest because the steering column is in the way..

SOURCE: 2001 astro chevy van 4.3 engines need to set the timing

The distributor in that engine can only be installed in one position. The hold down is built onto the distributor meaning when it is installed and the engine runs the computer is responsible for the timing. The distributor will move a little but won't correct major timing errors.

SOURCE: Need to change thermostat in 01' Chevy Astro Van

It is located where the big hose comming out of your radiator connects to top of engine. Remove hose from engine your thermostat is undernieth

Harvey N Tawatao

• 3854 Answers
• Posted on May 31, 2009

SOURCE: Sticky throttle on 200 Chevy Astro

There was a recall on the throttle body blade on the 4.3 a few years back for the throttle body to stick in the close position. Yours being 9 years old makes me think that there not going to do anything for it but give you the solution to the sticky throttle blade.
The solution was to change the blade. You can try cleaning the throttle body blade by spraying throttle body cleaner in to the barrel of the throttle body. If you look down, you'll see the carbon build up and it may just need and good cleaning. 
If that does not work, you can buy a new Throttle body blade which is only held on by two screws on the throttle blade shaft.

Start with cleaning the blade and throttle body with throttle body cleaner. Just follow the instruction and you'll be fine. 
Keep me posted and good luck.

SOURCE: 98 Chevy Astro van AWD

I'd check for vacuum leaks next. use a spray can of intake or brake cleaner. spray around vacuum lines, manifold gaskets etc. if the rpm increases you found a leak.