Expert: Robert Summers - 8/12/2009

Question
I have a 99 chevy silverado with a stock 5.3 100,000k. My problem is that sometimes when i go to take of the truck will bog down. If i push the petal more the worst it gets. Afterward the acceleration will kick in like i just stomped on the gas. I heard it could be a vacuum leak,if not could you tell me where i should look for the problem. Thanks for any help you can proved.

Answer
Hi Chris.... well that lag in the throttle could be caused by a couple of differant things... could be a vacum leak usually in the intake...could be fuel inj problem or an ign problem.. quick check for a vacum leak is to take some air intake cleaner and spray around the intake...if you get a sudden increase in RPMs while doing this you may have a leak...check all vacum hoses as well for cracks or sucking themselves closed... if all is ok there then try some good fuel inj cleaner or have inj flushed... the other thing that can cause this is poor ign referance... check all your ign components for any cracked or frayed wiring, dirty or corroded connections, dirty crank sensor....when all else fails install a scan tool and see if you have any codes...hope this helps