Egine runs rough while idling

**Bear945** · 09-07-2009, 07:32 AM

Well I really hope someone hear can help me. I have a 08 silverado 1500 LTZ w the 5.3 V8. From day one when ever I stop at a stop light the engine runs rough and the tach jumps up and down like a yoyo.The engine also acts like it is getting starved for gas.I have had it in the dealership several times and they say this is normal. I have 8,000 miles on it.Thanks to one and all.

**spazzoid13** · 09-08-2009, 04:36 PM

not normal
do you happen to have what sounds like a vacuum leak? the one time mine did that, my (correc me if im wrong) PVC valve was uncovered and was sucking air and causing it to act same. I would pop the hood in the drive way and leave it in park, and see if anything sounds amiss. or goto a different dealer/shop.
how much does it jump?

**vncj96** · 09-08-2009, 11:44 PM

Take it to another dealership for a second opinion, I can tell you that my local Chevy dealership is a joke and dont trust them one bit, so my family goes about 25 minutes away and its night and day difference for service, sales and showmanship

**Bear945** · 09-11-2009, 02:09 PM

i will try both ideas. The tach moves about a 1/8 of a inch.
Thanks for both ideas I will let u know.

**gernest2** · 09-12-2009, 04:21 PM

I had the same problem with my 03 silverado... I took off the throttle body cleaned the carbon build up with throttle body cleaner and I cant stress enough "throttle body" cleaner dont use carb cleaner cause it will damage the sensors in your throttle body. put it back on and its ran like a champ since.