fuel trims stuck rich supercharged taco

[Tadias48]

I've been having a problem where the fuel trims are stuck at -20% on a trd supercharged tacoma. 61lb urd injectors. the truck previously ran a ucon piggyback and since then i have pulled it off. it keeps showing -20% on the trims regardless of the changes I do to the tune. The eq1 and 5 do change but they eventually go to 1.18 lambda and I keep getting a stuck rich code. both o2s are new as well a fresh rebuilt engine. the gauge pegs 18 on the wideband as well as my dyno wideband. Have any of you guys ran into something like this ??

[Tadias48]

so i went back to the 45 lb injector size in the tune leaving the 61 lbs in the truck to see if i could run it richer to trick the ecm since its pulling -20. well now its pulling 40% there's no table in the tune I can see forcing the EQ request at 1.21

[SlowNStock]

so i went back to the 45 lb injector size in the tune leaving the 61 lbs in the truck to see if i could run it richer to trick the ecm since its pulling -20. well now its pulling 40% there's no table in the tune I can see forcing the EQ request at 1.21

That's "correct" behavior when you move the injector constant in that direction - the injector constant is used in the IPW calculation, and a larger constant (smaller injector) results in additional fueling. The extra fueling is, in turn, pulled back out by fuel trims during closed loop.

Looking at your attached tune, your injector inverse isn't scaled by the same factor as your injector constant; the calculation should be:

Old Injector Constant / New Injector Constant * Old Injector Constant Inverse = New Injector Constant Inverse
14.141250 / 7.335 * 1.54340 = 2.97554

You're also using the factory injector offset data, which should be updated for your current injector. Those are relatively minor, though, given the large fuel trims in the attached logs.

The 18+ AFR you're seeing at the wideband is questionable given the feedback you're seeing from the onboard sensors. Looking at your DTCs, it appears you may be running something non-OEM on the exhaust side, so a leak is always suspect given the disparity between readings.

Are you still using the factory airbox?
Are there any other modifications to the fuel system?
Have you verified fuel pressure?

[Tadias48]

I've attached a log and tune with the new inverse and scale. same issue. something is requesting the ecu to command 1.2 eq and I don't see any table that will do that. i could run it open loop and tune that way. my concern is this truck is going out of state and I rather have the ecm make adjustments for environment differences if it can.
The taco has the TRD airbox from the supercharger kit. it was previously ran with a ucon piggyback. it now has a new ecm thinking maybe the ecm was bricked or damaged. at this point im at a loss and dont see anything in the tune asking for 1.2 lambda

[SlowNStock]

I've attached a log and tune with the new inverse and scale. same issue. something is requesting the ecu to command 1.2 eq and I don't see any table that will do that. i could run it open loop and tune that way. my concern is this truck is going out of state and I rather have the ecm make adjustments for environment differences if it can.
The taco has the TRD airbox from the supercharger kit. it was previously ran with a ucon piggyback. it now has a new ecm thinking maybe the ecm was bricked or damaged. at this point im at a loss and dont see anything in the tune asking for 1.2 lambda

If you go back to all the stock settings other than the updated injector constant and inverse (attached), what does your log look like?

[Tadias48]

So I finally got to the truck again and flashed the new edits tune. It did the same thing EQ desired went to 1.20 and fuel trims are stuck at -21% unfortunately the log corrupted somehow and didn't record it all or save properly.