2011_XLT_5.0_4x4_137,000kms

A couple of months ago the money light popped on, scanned it with my Torque Pro app and got a singular code P2098, so driver side downstream O2 was reading lean.

This code on it's own could be several things from leaky exhaust, vac leak, bad MAF, bad CAT, bad O2 sensor etc... I cleared it once and it came back a week or so later, I cleaned MAF and it cleared itself a few days later, then was off for weeks and came back again recently. I would monitor some data on my Torque app while putting around town but nothing really looked off. I did notice the last time the light came on it came on all three times at the same stretch of hwy on my way to drop the kids off at Grandma's for a visit, about 30 mins into the hwy drive.

So, I turned on the app to monitor read outs on my next hwy drive and at pretty exactly 30 mins into the drive with cruise control on, my downstream driver's side O2 sensor suddenly dropped voltage (lean) and my short term fuel trim on driver side shot up to compensate...Anyone see or think of any reason not to just condemn the sensor?

 

I'll call this one fixed. I changed the driver's downstream O2 sensor near a month ago, the light went out a few days later by itself and hasn't returned. I tested the old O2 sensor with common methods in youtube videos and it passed all of them, I don't know why it would suddenly lose it's voltage 30 or so mins into a hwy drive, but the new one isn't doing it, so score another win for the Torque Pro app, great $5 investment.