Innovate LM2 Wideband Info

[vsslpr]

I probably will edit the history tables. I havent really looked at tuning spark yet anyway but would the guide to tuning with 12p be a good start for info on spark tuning methods (i know the fueling is different due to map vs maf)?

[Holden202T]

it may be ok for giving you a general overview but there will be differences in how the map v's maf systems work for spark and fuel.

as far as knowing which table to edit etc its more a matter of learning how the system your using works and going from there.

for example, with 12P when logging target AFR v's wideband you can see in the logs that when you come to idle the target AFR will be 14.7 but then after 20 seconds it will sharply drop to maybe 14.2 etc, this is when it switches from open loop to idle AFR table.

so in 12P there is a scalar how long after coming to stop before it will change to idle AFR table .... this is the sort of stuff you need to learn and unfortunately it takes time and practice for this side of it.

also I would recommend stuff like this be changed after letting the car come to idle and settle itself, if its still changing IAC steps or adjusting AFR from one table to another its only going to skew your readings and make tuning really hard.

also that said, I wouldn't so much worry about what numbers are in idle v's open loop AFR tables, more so just make sure your wideband matches the commanded....

you'll find unless you have a big cam or such then you wont need to change the commanded numbers, rather just adjust the tune so they are actually doing it.

so in the below example,

monitor 2
blue trace = target AFR
green trace = wideband

I know its not the best because its methanol AFR's but you can see at the 9:12 -> 9:16 second marks this is holding the car on the start line on the brake and the ECM is commanding 6.4 AFR (same as 14.7 for petrol) then as the green light comes on I nail it and go through the gears its switched to the open loop AFR table (and in this case also the boost AFR table).

open loop afr is commanding 5 AFR (right on the 9:16 mark) then it quickly drops to 4.8 AFR (boost) and then the wideband is fairly closely following it but there is also a rich spike on WOT (9:16) which I have yet to tune properly.

dizzy trace2.jpg (132.07 KiB) Viewed 5297 times

also disregard 9:24 onwards, I had some electrical issue there.

[vsslpr]

so the wideband is quite accurate (assuming correct calibration) and should be very close to commanded afr.. so.. if my wideband isn't following commanded afr closely on a completely stock tune then would that indicate problems in the fueling system? or is the factory tune just crap and its basically not really controlling afr too well?

it may be ok for giving you a general overview but there will be differences in how the map v's maf systems work for spark and fuel.

as far as knowing which table to edit etc its more a matter of learning how the system your using works and going from there.

for example, with 12P when logging target AFR v's wideband you can see in the logs that when you come to idle the target AFR will be 14.7 but then after 20 seconds it will sharply drop to maybe 14.2 etc, this is when it switches from open loop to idle AFR table.

so in 12P there is a scalar how long after coming to stop before it will change to idle AFR table .... this is the sort of stuff you need to learn and unfortunately it takes time and practice for this side of it.

ye im slowly learning taht kind of thing just digging up forum posts etc and asking questions basically i havent made any changes to the stock cal yet because I wanna make sure everythings reading right and accurate and fix any issues before i get into tuning!

[VL400]

You have lots of unknowns, but there is one sensor that is very accurate at telling you if your rich or lean from stoich - the narrowband sensor. Its been suggested a few times in this thread, use them as a check of your wideband around stoich.

This is from Innovate logworks, Wideband is pink and the narrow band the lower trace during closed loop..

Closed_Loop.jpg (36.77 KiB) Viewed 4799 times

The narrowband drops well below 450mv as soon as the wideband AFR is leaner than stoich and goes well above 450mv when its richer than stoich.

[vsslpr]

is that from your log?

looking at this trace from an idling log here my wideband is out by heaps- commanded afr is 14.3 (14.25 from idle table) and narrowbands seem to be showing that (not sure their range and the conversion from mV to afr but at least they're showing richer) wideband on the other hand shows way leaner..

o2 wideband-narrowband.JPG (79.8 KiB) Viewed 5274 times

[VL400]

You need confirm that the wideband AFR shown in the TP log matches MTX-L display. Same test, get it idling and compare the MTX-L display and what TP shows.

[vsslpr]

yep that side of it is sorted gauge and TP5 readings are spot on.. do you think my w/b sensor is dodgy?

[VL400]

If you are confident that TP and the gauge display match then see what happens while driving and its in closed loop. You should see the narrowband swinging between rich/lean with the wideband swinging either side of 14.7:1.

[vsslpr]

I have a log of that here's another run i did with a long idle period at the start and then normal driving conditions with closed loop enabled and here are the traces
idling- open loop

idle.JPG (76.3 KiB) Viewed 5255 times

driving- closed loop

closed-loop.JPG (108.76 KiB) Viewed 5255 times

in this log idling wb afr seems to be pretty close (so its a bit inconsistent with the other log only idling) the driving trace (same log) shows typically the behaviour of the wideband reading- its usually high like that and doesnt really swing either side of stoich its even read 22 (or whatever the max is) before driving on the freeway and coming off the throttle spikes the wideband afr reading to max!!

[Holden202T]

that does look a bit odd.

i'd maybe suggest running through the free air calibration again just to double check that side of it.

I assume this is a relatively need MTX-L ?