MAF Gen-2 + LM-1 + AFR Tracking

[granatl]

Assuming that I have no narrowband O2 sensor, what is the correct wiring to do the AFR tracking with an Innovative LM-1 as my wideband?


LM-1 (NB out) Gen-2 ECM
Red Orange
Shield Purple
Black Purple

(and then set the LM-1 output range on both A&B to 0-5v)?

To be clear is the Gen-II simply changing the MAF-to-fuel curves to control the AFR? I was originally thinking that the Gen-II would "pass along" the narrowband signal across the gray wire to the purple wire at the ECM

 

[TurboBob]

how is the gen2 wired into the car? plug-and-play or wiring connections?

yes, you need to program the LM1 to match one of the other popular curves (I don't think the native LM1 curve is in the gen-2)

yes, the wideband tracking is manipulating the MAF signal to the ECM to correct the AFR. the O2 connections on the Gen2 (orange and purple) are an input to the Gen2.

what chip are you running?

Bob

 

[granatl]

I FINALLY got everything straightened out. Hopefully, my mistakes will help someone else in the future.
When using a MAF Translator Gen-II with an LM-1 wideband, you can use both outputs of the LM-1 with one feeding the Gen-2 and the other as a substitute for the narrowband O2 sensor.

On the 1/8" stereo headphone jack coming out of the LM-1, red is the Analog 1, while black is the Analog 2 (silver is signal ground). [you can also reverse the red and black, just be sure to switch the volt-lambda values too]

Wire the LM-1 red wire to the Gen-2 orange wire. Wire the silver LM-1 to the purple Gen-2 wire.

Wire the LM-1 black wire to the purple wire on the ECM (the one that is normally the narrowband O2) sensor. Make sure to either cut this wire, or unplug your stock sensor.

On the Gen-2 set the wideband input as LC-1 (this apparently gives better lambda resolution than the LM-1).

Using the serial cable to the LM-1 and the LM Programmer software, set the following in the Analog 1 tab:
0V = 0.5 Lambda
5V = 1.523 Lambda
(click the program button)

Switch to the Analog 2 tab:
1.099V = 0.958 Lambda
0.103V = 1.022 Lambda
(click the program button)

Don't forget to set the various parameters in the Gen-2 which enables AFR tracking.

Now. Does anyone know if the Gen-2 can, in turn, output the same voltage that it's seeing from the LM-1, so that I could feed it into the input block of the PowerLogger (to then track the wideband AFR)????

 

[TurboDave]

I don't think you can output that voltage from GenII, but what everybody else does is tap into that wideband signal feeding the GenII and send that signal to the analog block of the Powerlogger.

 

[TurboBuRick]

X2 what Dave said.

If you want to watch tracking on the powerlogger, send analog out 2 from the gen2 to the powerlogger I4 or I5. Set analog out 2 to correction factor in the gen2. In the powerlogger set up page set I4 or I5 to correction factor as well. Now you can watch wot correction on the powerlogger graph.

As far as using the wideband to input narrowband signal to the ecm, you are better off leaving that job to the stock o2 IMO.

Glad to see your working things out. The gen2 is a great little device.

Rick

 

[granatl]

Thanks guys!

 

[bpman1234]

love this site .and the gents that give there time .

 

[granatl]

OK, I'm feeling rather dense. I connected the gray Gen-2 wire to the PowerLogger I4 and set the config parameter to correction factor. Most of the time, I just see -25.0%; I assume this is because there's some thresholds to hit before AFR tracking begins? Even so, the "highest" I ever see logged is 0%.

So, I unplugged the ECM to reset the BLM's back to 128. I set my Extender Extreme G to "open loop always" and, quite frankly, I just don't get it. I push the mainscale up to ~40.0 (running E85) and the wideband is right around 14.7.

So, am I to increase the "floor" of the low/mid/hi tune to a high number, then set the "MAF Sensor Tune" using the percentages given by PL for the correction factor? Once "respectable", then re-adjust the floor of each and fine tune from there?

I know one thing that's consistently throwing me off is the Gen-2 says MAF 4 g/s, but PL is showing a different number. I assume this is because of the bit twiddling to handle the 768 g/s. This causes me to get confused on which Gen-2 parameter I really should change. Any tips?

 

[TurboBob]

post some logs.

the gen-2 is reading the sensor value, but when you make "adjustments" it changes the signal sent to the ecm, so I would expect the readings to be different. remember to set the MAF range in the PLC program to 768 (to match the Extreme G chip)

for large full-range shifts in the tune (like if your chip doesn't match the injectors, etc) try using the "mainscale" adjustment, since it affects the whole range. use this to get the tune so that the car runs 13.5:1
when cruising (this is the afr target in open loop).

then tune the individual tuning ranges for best driveability.

Bob