I was thinking of going ahead and wiring up my Innovate Wideband permanently for both wideband and narrowband integration to the ECM. The wideband 0-5v signal I'll bring into the DIAG2 port of the 730 ECM, and the simulated NB signal I will bring in as the standard O2 signal. Just have the wideband, no regular O2.

I'm sure it will work to some extent, just looking for some input from someone that has tried it out to get an idea of what to expect in terms of good/bad.

-Craig

 

I've had my LM-1 running on my PCM in NB simulate mode for about 10k miles (I never bothered to weld in a second bung). It has worked flawlessly. Not one trouble code. I don't use it to tune part throttle BLM's though it would probably work halfway decent. I used the NBO2 for that. I calibrate the LM-1 about once a week when in DFCO mode, that way I don't have to take it out to do the free air cal.

 

What would be neat is if someone would write a patch for just using the WB's WB input, and then you could set the rich lean points, and really change the light load AFRs. Maybe, even a lookup table for light load AFRs.

 

I've been working on this type of patch for the 7749 ECM for a while. It's interesting how many details there are in the existing code for fuel corrections.....

Here's what I have so far :
1) Lookup table to convert WB voltage to AFR
2) Lookup table f(MAP,RPM) for "warm" desired AFR. (There's already a lookup table for desired AFR when engine is cold.
3) Rudimentary Proportional/Integral correction.

I've had problems determining when the WBO2 sensor is really "ready". The NB sensor has a known behavior when it's not ready such that the code determines this and remains in open loop. Two problems with the WBO2 present itself. First, does any one sensor have some sort of characteristic that can be used by the software to determine the reading is valid? Second, is this common for *all* sensors..?

Now that I think of this more, how does the simulated NB output of the WBO2 sensor handle this? Does the NB signal behave just like the NB sensor when "not ready"?

 

Hmm... wideband o2 sensor is faster reacting to AFR changes than a narrowband, even a new narrowband! I see no problems so long as the circuit was proportional to the actual AFR and not just a digital switch.

 

Not looking thru the code, I'd imagine that the loop runs for a given number of cycles and then switches back to closed loop. Wish I had time to check this...