Random Misfire / Idles Rough Always Missfires

[Servtex]

Alright this is a total nightmare some of you might say why havnt you taken it to a gm technician yet, and the reason is where I live you get your vehicle into the shop it doesnt come out for a month and you have a couple grand wrapped up.

 

Here it is

 

2005 Chevrolet Silverado

5.3L Automatic

2 Wheel Drive

 

You start the truck and it missfires the truck bounces around. When you take off it missfires and acts like its gonna die then it takes off and if your at high RPM highway or just flooring it it will backfire everyonce in a while but for the most part runs normal up at high RPM.

 

Things I have done and trouble codes I get

 

Random multiple misfire detected

system to lean bank 2

 

I have replaced

Fuel Pump

Plugs + Wires checked gap on plugs to .40

Crank Sensor

Took apart the throttle body cleaned every inch of it with a tooth brush and cleaner

took apart the injectors cleaned them

unplugged each coil pack to see if it would run any different

mass air flow sensor

bank 2 02 sensor right before the cat

cut the cat off to make sure it wasnt clogged

 

 

WHAT ELSE COULD IT POSSIBLY BE

this is rediculous this truck should be easy to diagnose since it has individual injectors, individual coil packs, if someone is wrong it should be with a particular cylinder not a RANDOM misfire

 

HEEEELLLPPP

 

Thanks Guys

[jro909]

lean bank means oxygen sensor if i remeber right...if the o2 sensor is bye bye the truck is running rich...otherwise hows the fuel filter and pressure regulator?

 

 

if your running rich, the truck could be pouring in way too much fuel leading to missfires and backfires from unspent fuel going into the tail pipe

 

p.s your local shop sounds like a shithole