4.0 1gre no power

i may mention my stft and ltft are above 26% floating between 19-26% on a regular

 

This is what I mean by fuel trim all over the board

 

Bank 1 will fluctuate back to 19.5 ish on and off also. Super confused

 

I've been doing some reading and I'm seriously wondering if the fact that I have a catless exhaust the reading the motor is getting is all out of whack. But no one sells o2 sims anymore. So I think I may have an issue with that

 

Have you checked for exhaust blockage or leaks?

 

Do you mean o2 spacers?
https://www.temu.com/ca/spacer-oxyg...1094&msclkid=78c930c6ae9a14c9c96554274f29347b
Best thing ever to eliminate Toyota over sensitive cat codes. Cured my high mile Sienna CEL

No cats... what are you doing with your o2's? You must have codes. With hard codes or even some soft codes youll go into open loop and yes youll have weird shit happen.

You can go catless but you've got to properly trick the system.

 

I already have a catless exhaust. And I have the sensors plugged in in the only spots they will.go. the sensors are not brand new, about the only thing that isn't. But they ran just fine before. Rather not replace them just because since the set is almost a grand

 

Just a visual to help

 

Do you have a wideband O2 sensor on there? If not, it'd help with any diagnosis and keeping the built engine healthy.

 

No I don't. I've never had it up and running 100% since I built it so I haven't added anything else to it. Do you mean a wideband guage? I've been using a scan tool basically to see my graphs on fuel trim and O2 voltage ect

 

Yeah, something like the AEM UEGO. That way you'll be able to see your A/F ratio directly without having to interpret fuel trims or voltages.

I haven't read all the posts but if you're running alright at idle and stumbling under load, I'd look at the fuel pressure to make sure your regulator is functional and the rate is rising properly, or look at the TPS or MAF to make sure the truck knows it's supposed to be asking for more fuel. Those last two should throw a code though.

 

It's actually opposite. Running like crap at idle like a bad misfire, but then when I give it gas it gets back to rhythm but I get lean codes on both banks

 

Apparently the higher the reading the higher the lean amount, so I get one side looking too rich and one side looking way lean on the scan tool. But my piggyback ECM should be giving the stock ECM a different reading so I'm utterly confused on what's actually going on to be honest

 

for anyone who cares to know. i figured it out. it was a vacuum leak like many people suggested. but it was a vacuum leak from a bad seat on an injector. traced it again to be sure and though i heard a noise by the middle. sure enough resealed my drivers side fuel rail and baam noise went away and fuel trims came back from lean. now i have a slightly rich mix going in all the time. which maybe someone has a idea on?