Need A Flow Chart And Checklist

[snoopy'sD-18]

My wife and I own a 2002 Chevy Silverado. My wife's pride and joy. The truck has been as dependable as the sun.... until the other day. The truck started to suddenly run rough as I left the house and died at the stop sign. I was able to milk her home.... My wife had to take the truck to work and it ran fine for two more days. then it happened again.... We pushed her home.... This is what I've done so far...

 

2002 Silverado 4.8L V-8 1500

 

Checked for vacuum leaks (manifold, throttle body, air inlet, etc...) and obvious connection issues.

Plugged in the reader and found one pending code, P0131 (Check engine light never came on)

The code led me to a "Upstream oxygen sensor (left cyl. bank) circut low voltage"

Then checked exhaust for blockage

checked connections on all four O2 sensors

Inspected for damage...

nothing....

 

I am a decent mechanic and I know from experience that throwing money and changing parts "Willy nilly" will get me no place. I just can't afford to take it to a dealer.... Just cant. If you would be so kind as to help guide me, that would be great and that would make my wife very happy too... Thank you for any help you could give me.....

[thearborbarber]

Have you checked the fuel pressure at the fuel rail? Any mods done to the vehicle?

[snoopy'sD-18]

The Truck is bone stock and I haven't checked the fuel pressure yet.... Plan on doing that this afternoon, after work... I also plan on a more thorough inspection of the O2 sensors and Cats....

 

Went and checked battery output and during cranking she never went below 11 volts.... Discovered a new noise.... A metallic clank coming from the gas tank area as the engine idled for a minute or so... the truck died before I could get exactly where the noise came from... Medium frequency intermittent clank, 2 to 3 hits per sec.... WAG.... Fuel pump....

[snoopy'sD-18]

 

O.K. Problem solved. It did turn out to be the fuel pump. Before I committed to buying a $300.00 fuel pump I checked fuses, and the relay just to be sure they were functioning right. Ordered the fuel pump from Summit, installed it last night along with the new connector and installed the tank today. I was careful to have a helper (my wife) so I could listen for the fuel pump and check for leaks after starting the truck. She fired right up and ran like she always has... Took her for a trip around town and now both my girls are happy....