What is the normal fuel trim range on a D2 4.6, I have not been able to find a good source of info. I believe I am running rich but I need to verify

I am planning my spring maint. So far I have :

• O2's mine are slow
• MAF peace of mind really I get an oddball 1170 every now and then

 

From researching my Toyota, it takes 20% +/- or more to trigger a code. The Rave should have the specific numbers and conditions to trigger a code. I'll take a look in a min but the codes should be emissions too lean/rich.

 

@Sandman614 i did a short run check driving home, about 20 minutes a one steep hill running 3200 for about 2 minutes 3rd gear. Long term/ short term/ sensor bank one on top

No codes thus far related to fuel, jsu tbeing proactive

 

You're numbers look good to me, and the ECU(no codes). I really wouldn't worry about it until you start going past 10%+/-.

Hmm, quite a difference in Toyota and LR documentation. Search still running for the 3rd set of terms through the rave, but heres some reading from Toyota.


Toyota O2 Fuel trims

LR fuel trim info

 

Nothing in the Rave which is odd

 

I don't recall where I saw it, but I recall reading that +/- 5% is normal fluctuation. Something outside of that for short periods of time is no big deal.

 

I wouldn't even be scared up to 10%

 

Just seems like the Disco has a bit less power, but it is "spring" in the Vancouver area which means more endless rain. But the O2's are definitely on the way out no nice clean patten very variable.

 

Up there in the frozen north it might be worth having a set on hand but down here I wouldn't worry about erratic O2 readings. They aren't really supposed to read too normally, reading the exhaust gasses and telling the computer to correct. In my auto tech class that was a complaint of mine, "why can't they find a nice smooth medium rather than seemingly over correct both ways constantly". If you blip the throttle WOT, you should see a sharp dip in O2 readings and a sharp raise in STFT readings(it might be the opposite). I've found the OBD readers a little laggy, so it might not be your O2 sensors that are reading slow.
Graphing the readings is probably the best way to view readings.

 

@Sandman614 Yea my one O2 reacts "normally" the other is weird, I graph them as I drive. The one side the peaks are all over the place.

I did discover my air filter has got some black tar like substance on it that was not there last month so likely no helping, a new one is on the way.

To be fair the Disco goes when I put my foot in it and runs smooth under power so it might just be me, my wife says I am a tad OCD about maintenance.