New LS Install, Back Firing, O2, fuel pressure issues

[peeblesj]

Hey Guys,

I have been searching high and low for information about my O2 readings and back firing. Little background, I just finished installing a 2001 5.3 w/ 4l60e. Got the computer reprogrammed by Brenden at lt1swap. I was initially having trouble getting the motor started and had to raise the idle set screw a bit. Was able to get it running, but not very good. Just finished putting about 6 feet of exhaust pipe on for back pressure.

My motor idles decent (about 1000 rpm) as of now but I will lower the idle. When I crack the throttle, it back fires a few times then is fine. Hooked up the scanner and I found the following graphs of the O2 sensor readings. Bank 1 Sensor 1 seems fine, but Bank 2 Sensor 1 just about flat lines for some reason.... I ended up switching the O2 sensors from bank 1 to bank 2 to see if the sensor may be bad, but the problem stayed in bank 2. Both O2 sensors are brand new...

Also, when I have the truck off and turn the key to run (not start) the fuel pump turns on for 2 seconds and the fuel pressure rises to about 45. Then drops right down to 0. When the truck is running, the fuel pressure stays at about 40. These seem low to me. Not sure if I am not getting enough fuel to Bank 2 or not....

Pics are the following: Top Left was the initial start up of the engine. Top Right was a couple minutes in so it was at close to running temp. Bottom Left shows when I cracked the throttle wide open for a second. Bottom Right shows when the O2 sensors were swapped from bank 1 to bank 2. Last picture shows my running fuel pressure which seems low to me. (Notice above each graph is shows B1 S1 for Bank 1 Sensor 1 etc)

Like I said, I have been searching this site for weeks and I have found a few things to try, but I figured I would post some pics and maybe somebody has had my problem and something sticks out right away. Any help is very much appreciated!! Thanks guys!