Question...Will a hard reset (removing neg batt terminal and touching pos terminal with ignition key on) *reset* my long term fuel trim values? I thought I did a reset once and I still was showing high LT Fuel Trims on my scanner.

I hope it will on my XJ6, just did the reset today and will find out tomorrow when I go out.

Removing neg. terminal and turning key to ON position should reset the trim values. I would also leave the neg. terminal off for about ten minutes.

What are your O2 readings and have you tested you FI's?

I don`t recall what the O2 readings were. I installed a new MAF Sensor and I want to reset the fuel trims. When I last did a hard reset, I didn`t leave the neg terminal for 10 minutes...maybe that is why the fuel trims didn`t reset. Thanks!

Yes, that procedure will zero your adapted fuel trims. But, if you still have an air or fuel problem existing, the Long Term will get right back up there in only a few minutes.

Cheers,

From the stickies
https://www.jaguarforums.com/forum/x...connect-74146/