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My 98 uses the VE table under full acceleration. I can control the AFR at WOT by simply changing my VE values. It took me a long time trying to tune the MAF and getting inconsistent results at WOT...

All I want is the derivative feature. That's gonna make things a lot easier for me.

You should first do a search on these forums...there's plenty of info on how to do this. Here's one link (of many):

http://www.hollandms.com/newbie/tuning_new.htm

You mentioned editor, so you can do that there. In the scanner, you can right click and select metric or imperial to get the same thing.

Right-click on one of the values in the table, select units and there you go.

You would have to increase the MAF flow by the LTFT value. The STFT's will always trend towards 0 since they are used to calculate the LTFT. Here's a good starting point:
...

I tried disabling COT, but no change.

I unfortunately don't have another WB, but since the NB agrees with the WB and if I do a run just under 100% TPS the AFR doesn't drop, I don't think that's...

Nononono, this is bad. Please take a look again at nc2-transition.hpl in the previous post. As described before, the AFR goes down ONLY when I hit WOT and not before.

It doesn't matter at what...

For your entertainment, here's a new scan where I don't force PE, so commanded is 14.4-15.x when cruising (please note that since I'm running open loop, the commanded AFR by the PCM is everywhere...

In this tune I force PE over 2000rpm (i.e. PE table set to 0), so I get 11.5 AFR unless I'm essentially off the highway. I can reset the PE table back so that I'll get 14.7 during cruising, but it...

Since I have been seeing different AFRs from the WB for similar MAF flows, I decided to just command the same AFR everywhere to eliminate that as a factor. This way I could see the AFR's response on...

Here's an even better one. In this scan I took a series of gradually increasing TPS to try to find the transition from high AFR to low AFR. You can clearly see that my AFR error% is 2-6% right up...

Thanks for the info. I'm impressed that you can run 18* without knock in that log!

Yes, I had the WB mounted in the B1S1 spot and the scan above had the cat installed. I indeed use the AC...

Tried removing the cat, but I have the same issue. Another way to look at it is that for any given MAF flow, the AFR reading is richer at WOT than at part throttle. I'm gonna try dropping the...

Well, after playing around with this some more, i am becoming convinced that the AFX is reading too rich at higher flows. Just looking at the log above, you can see that during the second WOT run...

Yeah, if I run richer then it helps, however most tunes that I've seen run 11.5-11.7 with similar mods as mine. I'm trying to figure out why this difference since I was hoping not to have to dump so...

Since my last thread went nowhere fast, I decided to try this out a different way. I have retuned my MAF fairly well using the open-loop method. Using the attached tune my AFR stays reasonably...

Just a few things I've noticed from your tune:

- MAF curve has a nice step in it and it is setup to read lower airflow than stock at high RPM's. Unless you know the MAF responds this way, I would...

Not to be disrespectful, but I'm not an idiot.

In the first post (I've been saying that a lot lately), I mentioned that I have been working on the MAF for a while. I've been using closed-loop...

That is exactly what I have been doing!

Below 7500Hz with narrowband (which coincidentally matches the wideband), and above 7500Hz with the wideband. Note that I am only having issues with the...

No, quite a few people use the standard interface with the wideband plugged into the AC pressure or EGR inputs of the PCM. The value shown in HPT matches what is shown on the AFX.

OK, I got a couple more traces tonight. On the first one I had to slow down due to traffic ahead. Scan11 looks better though. Even with all the extra stuff disabled, I still get a descending AFR...

Here you go...but the PIDs.txt already is a cut and paste from the scanner.cfg.

The Wideband output is seen by using the PID's in the first post. I've attached a config below which might help.

3. I go out and do a WOT run. Refer to Scan2.hpl from the first post. Taking the AFR error data from cells 8125 to 10375 (other cells were missing or otherwise unreliable). I paste multiply by %...