Bee*R ignition cut issues on the PowerFC. Works fine on the stock computer!?

[JZA70 R]

My friend and I both bought a Bee*R rev limiter each to install on our JZA70's.

We both have powerfc's installed but also kept our stock ecu if we ever needed to swap back.

We both installed the Bee*R according to this guide here.

http://www.toymods.net/forums/showthread.php?t=36902

Both Bee*R's work great on the stock ecu's however when we plug the power fc's in, the Bee*R causes problems.

The problems are...
When the Bee*R cuts ignition, it causes the powerfc to go into what i think is limp mode. It stalls the engine and the engine light will come on briefly, but not all the time. The motor doesnt stall completely, it will return to idle, then if your foot is still on the accellerator then the revs will pick up again until the Bee*R cuts ignition, then the whole process is repeated.

Does anyone have any suggestions as to what could be so different between the stock ecu and the powerfc as to cause this problem.

-The powerfc is a plug and play ecu.
-The Bee*R is installed in the cars original loom.

If people really need, i can show them what sensors on the powerfc are being turned off or on when it goes into this limp mode. If required i can also show video of its behaviour on both ECU's. This goes for both cars that are having this problem.





below shows which wires are required for installation, this is from the japanese Bee*R website.







below shows what those wire are...

[MR22ZZ]

why do you even need it?

the Power FC has an adjustable rev limit on it anywy.

[gwilmarlio]

its not for the rev limit that we need it for its the launch control and flat shifting
O and BTW I am the friend with the sam prob

[jeffro ra28]

why do you even need it?

the Power FC has an adjustable rev limit on it anywy.

So it goes bang pop fart when on the limiter..........

[sw20r]

on the pfc unit, cancel out the IDLE IG option in ETC and see if this helps?

[JZA70 R]

pretty sure ive already turned off ignition idle assistance but ill double check anyway.

[gwilmarlio]

on the pfc unit, cancel out the IDLE IG option in ETC and see if this helps?

I just checked mine and it was set on but even after I turned it off there was no change

[Smokey228]

If either of you guys decide to ditch the PFC, i'll take one lol

Where did you guys pick them up from, or was this before they stopped making them>?

Cheers,
jase

[gwilmarlio]

I brought mine over 12 months ago 2nd hand just after thay stoped making them wish I had a pro but if I can get the Bee R to work it will be a better gain just gota get it to work so if you know how let me know please

[82MKII]

Looking at the connections that are made, I guess the Bee*R unit is shorting the NE (crank angle sensor) signal to ground when it rev limits. I think IGF is a feedback signal from the igniter, so grounding this won't achieve the desired result.
I assume this causes:
a) the PowerFC to stop sending ignition pulses to the igniter; and
b) the PowerFC to get annoyed due to the lack of a crank angle sensor signal
c) the Bee*R unit then releases the short as the revs decrease and the PowerFC starts sending ignition pluses to the igniter again.
Does the PowerFc report any trouble codes?

All the above is purely my speculation, but with only 4 wires (two of which are power & gnd) it shouldn't be too difficult. The best way to be sure would be to stick an oscilloscope of the IFG & NE signals when it is limiting and see which one is getting shorted to ground.

Regards

Peter

[JZA70 R]

i presumed it was shorting the ignition signal to the ignitor rather than shorting the rpm signal... i have heard some toyotas incorperate a ignition feedback system and this is why GIZMO who also sell a rev limiter DO NOT make one for toyotas... the strange thing is its working on the stock ecu, it does work on the powerfc but once it hits the cut it doesnt recover normally because of what i assume is the ecu going into limp mode.

i have looked at the sensors switching on and off during this event but havent got a firm answer as to what sensors are doing what. ill have to log it and get back to ya.

[gwilmarlio]

dude I wil bring the logger with me sunday

[82MKII]

If you haven't already, have a read of:
http://mkiv.supras.org.nz/articles/engine_2.htm in particular code 12,13,14.
Interesting info about how NE & IGF are interpreted by the ECU. I assume this is probably relavent for the 1J as well, and you would *hope* this is what the PFC is doing.

Unless the Bee*R unit is really clever, it looks like it must be shorting IGF (rather than NE, as shorting NE should throw a code). If your rpm limit was lower than 3000 though, it should have thrown a code 14.

[JZA70 R]

thats the thing, its not throwing an error code on the stock ecu. its only the powerfc that is having troubles... i still havent got a chance to jot down sensor activity sorry.