MAFT-Pro VE Table

[CRE]

If you are tuning with a laptop in the car, and you have an AC adapter that plugs into the power outlet in the car, make sure you unplug this and run the laptop on battery only when you are tuning for idle!

I've found that the intermittent power draws made on the system with the AC adapter plugged in play havoc with the AFR's, vf, etc but only at idle.

When you are driving there's no problem at all with having the adapter plugged in.

I'd love to find out exactly why this happens... maybe something to do with the draw on the alternator being high at a point when it cannot produce much power due to the low rpms.... but wouldn't the battery make up the difference? I dunno...

Jim

I've experienced this as well. For me it ONLY did it when ALDL was connected. I could have the laptop physically connected, but not ALDL and everything was fine. Connect ALDL and my AFR's shifted by as much as 3 integers!

EDIT: The only two possibilities I could think of are voltage offsets due to running off a different circuit in the car, or an offset created by the laptop's power adapter.

 

[drjonez]

...or an offset created by the laptop's power adapter.

or poor grounding within the power adaptor.

are you guys using DC-DC adaptors or a DC->AC invertor to your laptop's AC power supply?

 

[CRE]

Mine is DC-DC. I'm quite sure this doesn't happen with my car. So far my laptop works fine with the adapter in my car. I guess I'll see if it happens when I switch to S/D.


EDIT: Oh, by the way Doc, don't worry about the shifting in my case. There turned out to be a problem with the MAFT Pro I was working on at the time, that may have been the cause.

 

[JimR]

My adapter is DC-DC. It's a car-specific 90w unit made by HP.

Input: 10-32v 11A Max
Output: 18.5v 4.9A

I use ALDL all the time and I noticed it would screw things up the most when I was doing things like doing a data upload to the maftpro, or when I was stopping and starting replays of my log files. Whenever I do an upload, the ALDL cuts out and things go haywire (super high afr's) at the same time.

After having tuned the idle with the adapter out, when I plug it in the AFR's go down to 11 or thereabouts, but vf stays at 2v (the middle of the range for me).

 

[Adjuster]

So, back on topic, any VE breakthroughs, or is the key to just run it, tune it so it's stable, then pull the plug on the stock O2, and setup your AF tracking for low/mid/high?

I was thinking the VE table setup was looking very promising... (And the MKIII tech site was down for what seemed like an eternity when I was looking at this last..)

 

[JimR]

So, back on topic, any VE breakthroughs, or is the key to just run it, tune it so it's stable, then pull the plug on the stock O2, and setup your AF tracking for low/mid/high?

I was thinking the VE table setup was looking very promising... (And the MKIII tech site was down for what seemed like an eternity when I was looking at this last..)

On the subject of pulling the stock 02 sensor, what's your plan to avoid code 21?

FYI I have been tuning for at least a year now using the VE table directly. I did this right from the start... my user tune values are all zero. I'm just getting ready to pull the stock 02 sensor and go permanent open loop so I can run a lean (16:1?) cruise using PTT.

 

[drjonez]

So, back on topic, any VE breakthroughs, or is the key to just run it, tune it so it's stable, then pull the plug on the stock O2, and setup your AF tracking for low/mid/high?

I was thinking the VE table setup was looking very promising... (And the MKIII tech site was down for what seemed like an eternity when I was looking at this last..)

no real changes, except the v5 of the software allows you to move RPM points around.

and yes, mkiiitech is STILL down. <sigh>....

 

[drjonez]

On the subject of pulling the stock 02 sensor, what's your plan to avoid code 21?

FYI I have been tuning for at least a year now using the VE table directly. I did this right from the start... my user tune values are all zero. I'm just getting ready to pull the stock 02 sensor and go permanent open loop so I can run a lean (16:1?) cruise using PTT.

AFAIK, there's no way around code 21. according to JJ, it doesn't have any affect of fueling or timing.

and yes, 16:1 cruise is delicious....heeeeeeeeeeeeelllllllloooooooooooooooo 30 MPG!

 

[DangoAZ]

Hmmm... Gotta love contradictory information:

Read post #30...

http://www.supramania.com/forums/showthread.php?t=39712&page=3&highlight=vf


I used to run my MAFT-PRO on just the WB with no NB at all. It ran like snot on a cold morning up top, but was a little bit rough around town below about 2,500 RPM. That and I would always get the CEL anytime I boosted 2psi going up a hill for more than about 5 seconds. I had read above post, and decided it was time for an upgrade to a new DP with 2 oxygen sensor ports, and went to running a narrow band and wide band together. I know I'm confounding with the new down pipe, and can't say for certain that it was all due to the computer having a feed-back to the NB again and nothing else, but my around town out-of-boost "driving like everybody else's Camry" driveability seems better with the narrow band hooked up.

I know there's a mod to the new version 5 that has a PTFB (part throttle, full boost) fix to keep from running 14.7 AFR when part throttle boosting and hooked up to the NB sensor, but I have yet to get that up due to the car being down with a BHG right now. Connection there? Maybe... maybe not. It was a stocker HG with 45K miles - done by Toyota via the previous owner. Long weekend ahead... To be spent disassembling and cleaning for new HG in the mail. The joys of Supra ownership, right?

TANGENT - Back on topic. Sorry.

So I guess you could:
a) Make a "freeway cruising" VE table that cheats the Vf up past 5 and let the MAFT part throttle track a 16ish tune for the freeway. Swap the VE tables with the lap-top for freeway trips.
b) Unplug the NB for freeway trips and part throttle track from there.

Most of all... Who's right on the timing/CEL issue with no narrowband connected? I'm certainly not the expert! :1zhelp: From everything I've ever read by JJ, I believe he knows what he's talking about. But I don't want to diss my fellow Supramania memeber from the other post without reason, either.

 

[americanjebus]

So, back on topic, any VE breakthroughs, or is the key to just run it, tune it so it's stable, then pull the plug on the stock O2, and setup your AF tracking for low/mid/high?

I was thinking the VE table setup was looking very promising... (And the MKIII tech site was down for what seemed like an eternity when I was looking at this last..)

Been using the VE table now for over a year and just recently starting using table 2. Problem i am facing with the setup is as follows.

Idle: if i blip the throttle while idline the vf signal will lock into 4.41v and stay there until the car drives around or starts taking some load. I have logs where it stays at 4.41 until i drive down the road and hit as much as 5psi of boost. I've seen this on 3 cars already. Why does the pro lock into 4.41.

Table 2: i switched to table 2 and the lower adjustments worked ok, but the farther i got into , well into the area where the car would run open loop i have to pull massive amounts of fuel from my VE table to lean it out. Is there something that needs to be done to activate table 2 other than the "config select" setting? the values for my ve table in the 5800rpm 220kpa range are in the 88's and the vf signal is still 0.0v @ 10.5 AFR'S

 

[JimR]

I can think of two things that apply here:
1. The ECU's default fuel map goes hardcore rich at WOT at those rpm's, so you'll have a lot to pull out.
2. The stock CT26 puts out far less pressure at the higher rpm's, so your VE would naturally be lower.

I actually have a VE of 77 from 4600rpm at 160kpa onwards. Check out my attachment in that "maftpro software graphics" thread for a visual. My target AFR from that point on is 11.5:1

 

[7MGTEsup]

Is there any way or re hosting Dowards VE tutorials as mkiiitech is still down and I want to get on with tuning via VE tables??