[Gregski]

I thought that once I install an LS engine in my truck I can put my Innovate wideband DLG-1 AFR gauge on the shelf, and I wouldn't need it no more as the PCM computer manages all that for me now.

I couldn't be more wrong! The O2 sensors on the factory ('99-07) GM trucks which we get our donor Gen III LS engines from use narrow band oxygen sensors, and all these sensors can say is Too Lean or Too Rich depending on the exhaust gases being emitted however they can not tell us how much too lean or how much too rich we are running. Which brings us to...

LS Lesson Learned #5 - In order to tune your LS engine you still need a UEGO (universal exhaust gas oxygen sensor) aka a wideband AFR gauge, word on the street is that the four wire won't do and you must use a fire wire O2 sensor. Now you don't need to run one in your vehicle permanently you can just unscrew one of the factory narrow band sensors and screw your wideband in temporarily as you tune the engine with your laptop.