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ECU Master Black missfiring and unstable state under the load

EFI Tuning Fundamentals

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Hi everyone!

I faced some issue with my 1JZ-GTE tuning: it runs pretty stable in idel, but RPM and Lamda starts hunting since I opened the throttal (see the screen)

Looks like have the missfire somehow and Lamda shows lean and reach mixture or anything else. Becouse of that I cannot keep VE table/base map tuning.

please, advise what should i check in order to fix it. Addtionaly I attached the log file

Thanks in advance!


Attached Files

There are some very smart guys here, but they are limited by the lack of information - if you can give as much information on your set-up as you can, they may be able to give help.

In the meantime, are you sure the ignition is up to the job of supplying a reliable spark - maybe try closing the spark gap to 20 thou - because any misfire will show as a lean mixture as the unused oxygen will be picked up by the lambda.

You seem to be targetting 1.3 for the lambda, this may be triggering a rich misfire, try dropping it to 1.1 and see if that improves things?

It does seem to be fairly regular - reminds me of a weird case where as the turbo' spooled up it would suck hard enough on the intake to partially close a hose, which dropped the air flow, which reduced the exhaust gases driving the turbo', which dropped it's speed, which dropped the suction to the point where the hose opened up and the whole thing started again - IIRC, a restrictive air filter was to blame.

I you want more help, you can attach your tune file. Your lambda values are all over the place.

But quickly checking the log, your injection angle is set at 65 deg, we usually see values more like 400-450 deg, but it depends on how your injection is set.

Your cam angle is bouncing between -25 & 429 degrees - which is obviously impossible, so I would say either the VVT is set up incorrectly, or the trigger settings are incorrect so it is losing 720 sync every cycle.

Thanks everyone for you advices! I really appreciate it. With help of ECU master tech support service i could identify my problem. THe problem was with secondary trigger due to wiring or faulty sensor (need to investigate). As temproral solution they advice me to disable the cum sync above 1200 RPM (see the picture). I apply it and my engine strat running stable under the load.

THanks again tpo everyone!


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