Hi I recently got a wideband air/fuel ratio guage cause my car is not running right it gots a stock 5.3 lm7(ls1 blew) and works fine until I floor it, The gauge says I’m running 14.5 just cruising but when I floor it jumps up to 19-20 on the guage and does not move or shifts just revs up it starts moving after a while I believe that means it’s not getting enough gas(running lean) I already swapped the tps anybody know why else this maybe happening? Please help.

 

Careful, you can damage your engine. Don't go WOT until you figure this out.

First thing I'd do is watch the regular O2 sensors during load for confirmation if you can, normally they'd go into PE mode and peg rich under load, what you are describing they will instead show lean. This will confirm your wideband is reporting/installed correctly and you are indeed running lean. You can use a cheapie ELM327 with Torque for this. The regular O2 test will also show that you're lean on both banks, which could be important.

Fuel filter and/or pump are obvious first things to check if car runs well otherwise. Throw a fuel pressure gauge on it and watch it under load and make sure it's holding pressure, if not find out why. I suspect a clogged fuel filter caused me to harm my original LS1 in my Trans Am years ago, back when I was new and stock and no wideband..

 

Thanks sounds good Ill do some testing and try figuring it out I appreciate it.