wiring / ecu experts on supra's and soarers needed within

[JZA70 R]

We have a Power FC designed for a JZA70 supra which we want to run a manual JZZ30 Soarer.

The JZA70 Power FC comes with a loom converter because the Power FC unit is actually a JZZ30 shell and they obviously reuse it for other models and include the neccessary loom converter for it all to work. I dont know but assume there are no firmware/software differences between the non VVTI 1JZGTE power fc's.



The problem we are having is that the Power FC will start and run the soarer but it will not idle for more than 5 seconds... If we pump the accellerator we can keep it alive but it will not idle on its own.

What could be causing this? ...Someone has suggested that the JZA70 Power FC cannot control the JZZ30 fuel pump system.

Cheers.








Below is a pic of the loom converter used with the JZA70... we simply remove this loom and the power fc will plug into the jzz30's engine loom... starts and runs but wont idle on its own.

[JustCallMeOrlando]

Bridge the FP wire in the diagnostics connector to run the fuel pump. If it runs with the fuel pump forced on, you're probably right.

[JZA70 R]

Ok thanks JCMO, is this a jzz30 diag port?



and do I bridge +B and FP ?

[Admiral coFF33]

correct mate! ^^^


Also as a side suggestion. It could be map sensor related.

[Admiral coFF33]

After you've tried FP + B+ ..... maybe try and run diagnotics check (E1 and TE1 connected together) and see what error codes you get on the dash.

[JZA70 R]

not sure the power fc uses or acknowledges the diagnostic port as it has its own internal diagnostics which you can view from the menu.

its not the map sensor as ive tried this on a total of three soarers with two different power fc's and they all do the same thing.

[wilbo666]

Bridge the FP wire in the diagnostics connector to run the fuel pump. If it runs with the fuel pump forced on, you're probably right.

Yep first thing to try

Cheers
Wilbo

[pandaah]

also try clamping the fuel return hose see if you can build up fuel pressure that way...

[bk_]

The problem we are having is that the Power FC will start and run the soarer but it will not idle for more than 5 seconds... If we pump the accellerator we can keep it alive but it will not idle on its own.

What could be causing this? ...Someone has suggested that the JZA70 Power FC cannot control the JZZ30 fuel pump system.

Cheers.

That would be me :-)

I've spent quite a lot of time analysing and implementing the FPCM (from some post-2000 toyota) on my 1jz powered car when i got sick and tired of having a fuel pump sounding angry, due to running at 14V. The way it works is that the ECU (OEM, maybe JZZ30/JZX90 powerfc sends this signal) sends a signal (via the DIAG wire) to the FPCM that everything is alright. Now in the case of the JZA70 PowerFC... this signal is NOT sent, thus the FPCM "slowly" shuts down the fuel pump after 5-10 seconds. This is a fail-safe mechanism.

For other people's interests, I do have a JZA70-based PowerFC Pro running on JZX90 / JZZ30 gear with the FPCM effectively bypassed. And can confirm that bypassing the FPCM solves the issue.

What I'd like to know is whether the JZZ30 / JZX90 based PowerFC works _without_ the FPCM since I vaguely remember the JZA70 has no FPCM.

Hope that helps.

[skin]

im currently having this problem in my jzx81 with jza70 power fc, so the best way to fix this is a perminent bridge in the diagnostic plug between +b and fp?

[bk_]

If it's an original vehicle with a FPCM up to the point of the diagnostics connector then yes.

[skin]

yea its jzx81 1jz factory fitted with jza70 power fc, i did it tonight its working good but if i leave ignition on pumps dont stop

[bk_]

But if ignition is off, pump is off?

I'm not sure how JZA70s are setup (they have a simple FPCM without DIAG wire?) but I've had the fuel pump configured in two ways for my custom engine transplant into a non-toyota:
* when IGN is on, FP is on.
* FPCM from JZS147, no problems with stock (and chipped) JZX90 ECU. But didn't work with PowerFC. reverted to the old FP wiring setup.

[RA35GT]

In factory setups the fuel pump is only on when the engine is running. (i.e. if the engine stalls the fuel pump should turn off!)

[skin]

yea it now turns on and off with ignition, its nice when it primes and stops until car is running where it then runs all the time, if you switch car off and leave ign on, the pumps arent going...
Its kinda noisy having 2 044 in the boot lol