First off I want to say what a great forum this is! I have been having problems with my truck for several months and this is the best forum I ...

First off I want to say what a great forum this is! I have been having problems with my truck for several months and this is the best forum I have come across. here is my problem: I have a 2006 Chevy Silverado 5.3 LT Vin B with 108k miles, I bought it used about 6 months ago and over the last few months have had what sounds like a misfire or exhaust leak, when I get on the freeway it hesitates pretty bad and sometimes surges when I try to accelerate. Took it to a great exhaust shop and they said it was a misfire not a leak. I thought maybe I got some bad fuel so I tried all the in the tank cleaners which did not help. I ran cleaner through my intake manifold to blow out carbon buildup. I thought it could be plugs or wires since they had never been changed. I replaced all plugs and wires, replaced the belts, cleaned the MAF, replaced the MAP, replaced 1 coil pack and rotated the rest one at a time around the engine with no change in engine performance, replaced all 4 O2 sensors and it still is running bad. So I kept checking around the internet and thought it might be a fuel delivery problem, since the truck does not have an external fuel filter I bit the bullet and replaced the fuel pump.....still running bad! I next suspected maybe one of the fuel injectors was bad, did the old screwdriver to the ear test and all of them sound like they are functional, I checked resistance on all of them and they are all around 12 ohms. (Could a fuel injector be bad if resistance is good and it is clicking?, maybe a bad clog?) I am really at my wits end with this. I don’t think the cats are clogged since it is not throwing a code and there is no sulfur smell. The only codes I have been getting is a P0304 when it surges really high (swapped coil pack on Cyl 4 and still got same code) So I am leaning toward a intake manifold leak or computer problem, Please help, I will try anything at this point. I think I will pay a dealership to diagnose since I am running out of ideas, I love my truck and I just want it to run like it should

Sounds like an intake leak to me. If you suspect fuel injectors are dirty, the easy way to clean them is to fill it up with a tank of Shell or Mobil premium.

I have scheduled an appointment a the local dealership and will update with what they find, thanks for your help

Sounds like taking it to the dealer would have been cheaper in the first place. Replacing parts gets expensive especially on the newer stuff. :/

I wanted to give you an update..after two weeks in the shop I have my truck back and it runs great. It had a bad cam shaft, there was a flat spot on cylinder 4 due to metal degridation, it cost $3200 to replace but luckily I purchased an extended warrantee so I only paid $300 of it. I am a happy camper 

amstone69 wrote:, did the old screwdriver to the ear test and all of them sound like they are functional,:)

Can someone please tell me what this screwdriver to ear test is? I am curious, thanks.

SuperChop wrote:

amstone69 wrote:, did the old screwdriver to the ear test and all of them sound like they are functional,:)

Can someone please tell me what this screwdriver to ear test is? I am curious, thanks.

That is when a mechanic uses a long screwdriver as a stethescope. I Usuallyused a long snap on brand unit that he touches one end to his ear and touches the other end to areas of various engine parts to locate noises. Usually the tip of the screwdriver will transfer noises from that ONE area to your ear to help locate a noise. You must be very careful of rotating parts. Steelman makes a headphone/amplifier version that will do the same thing. Hope this helps.