M84 2JZGTE VVTi Startup File

[xgrapher]

Yes I have the correct curve and that's how I actually started. Also when making significant changes reverted to them.

Today I took a video of the afr and the fuel table that shows how dramatic changes happen in the afr with very little changes in the cell values.

At 2.2 pw the afr reads 16
At 2.3 pw the afr read 11.8

All this happens in the same idle region. I'll try to upload the video and post a link here.

Also this tuner friend of mine is coming tomorrow to check it out for himself.

[xgrapher]

This is the video:

https://youtu.be/3MvyT1K2SFA

[SprinterTRD]

Big injectors will have this issue at IDLE.

Hopefully you have set the REF/SYNC so you are tuning the engine in sequential mode.

Load in the correct battery comp for the injectors and forget about them.

Have you set the correct injector current for the injectors?

Also your engine temp is at 65C wait till it gets to 80 C before tuning the main table. Is there any cold start compensations active?

The air temp is also at 58 C are there any compensations added from this?

As I wrote before Make your IJPU value smaller and say yes to modify the table. This will make each .5% change in the table a smaller injector opening increment.

Is your tuner friend a MoTeC Dealer or a person who uses MoTeC's all the time? If not find someone who does you will have less issues.

Many people have tuned 2JZ's with no issues

[xgrapher]

All compensations are off.

Most cars that I've tuned so far were between 800 to 1000cc injectors but didn't see such thing happening.

What if I went with an IJPU of 3 lets say? It will give me a very big resolution, besides Motec allows you to enter in values above 100. Because IJPU of 6 didn't do that much of a trick for me.

Also I'm going to plug in the Haltech again and check the Actual Pulsewidth to see if 2.2 to 2.3 can make such a dramatic effect.

[Sean]

At 2.2 pw the afr reads 16
At 2.3 pw the afr read 11.8

Is that actual pulse width or effective pulse width? And did I miss it, what is the fuel, and fuel pressure?

[Sean]

Ok, done some checking of log files and some reading, in my application with id1000's, car idles fine with an actual pulse width of 3.4 which gives an effective pulse width of 2.1 ish...... Our application is n/a 825cc a cylinder on e85, and it idles like a street car.

Yours is 500cc a cylinder, and I'm guessing petrol... What i think is happening is that with actual pw of 2.3 your effective pw will be in the early 1's, right in the zone where the injector flow changes radically with very tiny changes in pulse width.

http://injectordynamics.com/articles/low-pulse-tech/ there's a graph in there showing the low pulse width performance of the id1000's.

Can you try something like halving the idle fuel pressure and increasing IJPU just to see if the injectors start to respond normally? Anyway that's my best guess for now

[xgrapher]

It's solved!

The tuner got it fixed after cleverly catching what my mistake was.

Ok, so this is a quiz for those who are interested. Look at the attached tunes, one by me and the other by the tuner. Compare them to see what fixed the problem. If you guys could guess what the problem was then I'm an idiot. If all you guys couldn't then Motec for sure is an Idiot!

[Scott@FP]

You *still* don't have the proper injector battery comp in it. For small engines they (ID) can provide you with a 3D battery comp table that works even better at low slope PW's.

You don't have a fine enough resolution in the main table for fine tuning, suggest IJPU between 2 and 4.
As is, a value of 10 in the fuel table is 1.2mS. (IJPU = 12, 100 in fuel table = 12mS)
Fuel table goes from 0 to 400 units.

MAP sensor is a 3 bar, so assume this is boosted, suggest using MAP comp which is not being used.

[SprinterTRD]

I didn't look at your ref/sync capture but you changed the sync edge

Also I saw yesterday in the video you had too much ignition timing at idle the video showed 22.6 deg

[Sean]

What are you saying, setting up the idle control made a difference to how it idles?