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G4+ Supra 2JZ PNP

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hi guys, installed the G4 pnp unit on a 1994 Supra US model manual transmission, calibrated tps and started perfectly adjusted a bit the AFR and the idle control and it starts hot or cold perfectly, but as soon as I start pressing the gas pedal the revs start to oscillate, afr jumps around and no way to make it accelerate standing still, I checked if there was any protection on and everything is off tried to check everything and nothing makes sense, any ideas would be helpful, as of course with stock ECU no issues. 

1994 Supra 2JZ Manual

Stock Engine, HKS intercooler full exhaust.

WhatsApp Image 2019-07-15 at 10.28.06.jpeg

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Can you post your map, Make sure all motorsport features are off gear cut and launch in particular.

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A log will be helpful, but as a starting point, your ignition table being 0 or negative just off idle is going to cause weirdness

image.png.f8736cd6994f1fa28ed46d7ae12ce832.png

Try setting these cells to say 15 in 500 & 1000 columns, and 20 in the 1500 column.

This will make it idle higher and mean you need to drop the idle valve numbers or adjust your idle screw, but it will stop the savage jump in power output between idle & 2k rpm.

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There is no cuts or limiting out of the ECU so can rule out any limits. As CJ pointed out that ignition timing is odd and should be corrected. 

Fuel flow has been checked? Pump is running?

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I think its something to do with your fuel pump control causing the pump to shut off or go into low output mode. The bit where your foot is flat, but your RPM is dropping is the key point for me. 

Can you get your wideband running so we can see if its going rich/lean while the revs drop at full throttle? Alternately, get a fuel pressure gauge/sensor installed?

Maybe try setting the fuel control cutover to something like 4k & 50% DC as a test, and if that makes no difference, try disconnecting pin aux2 from the ECU and applying straight 12v to it (which should force the pump to high throughput mode)

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Thanks for the pointer CJ and Simon, 

The car has an NTK AFR display but I haven't been able to get the output to work so I ordered an AEM one to be sure I can work with it. The AFR goes to lean when i do the WOT. 

The strange thing is that the fuel pump was working fine before changing the ECU as I drove it from clients house to my office, I haven't checked fuel pressure but I will get it checked. 

Other thing I am having issues with is the AIT, I installed the IATB Bosch sensor is 4°c above ambient or ECT and i haven't figured if there is a way to calibrate it. 

I attach my actual version just in case I need some type of firmware update. 

link.png

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lambda going lean would line up with fuel delivery problems.

Because you have it working with a factory ECU we can likely rule out mechanical issues - blocked air or fuel filter, faulty fuel pump, bad regulator, etc. Based on this, this only this I can see in the config that would impact fuel pressure is if the fuel pump isnt being controlled properly by the link ECU. I'm assuming all the pinouts etc are correct, which just leaves the fuel pump control being wrong - maybe its not sending the right signal to run the pump at full power, maybe the PWM signal needs to go to 12v instead of ground or vice versa. Looking at the wiring diagram, these dont run a simple on/off relay, but a separate fuel pump controller, and there is a pin that is PWM'd to tell the fuel pump controller how hard to drive the pump.

My money is on the config for this pwm signal being wrong (or maybe on the wrong pin, so it stays on low power at all times) - hence my suggestion that if you dont see any improvement from ecu config changes, put ground or 12v straight to the controller so it runs full power, then you know what the voltage needs to be and can work backwards from there to make it happen.

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Your fuel pump set up and the fuel pressure increase solenoid on ign 8 all looks to be ok to me. 

Have you actually tried adjusting the fuel?  You say "stock engine" but the master fuel is set to 8ms.  8ms would be typical for injectors around 1000cc.  If you have the stock 440 or 550cc injectors then the master will likely need to be more like 13-20ms.

 

5 hours ago, sama said:

Other thing I am having issues with is the AIT, I installed the IATB Bosch sensor is 4°c above ambient or ECT and i haven't figured if there is a way to calibrate it. 

That doesnt sound like anything to worry about to me.  If you want to do a more scientific test, pull both sensors out and hang them in a cup of ice water.  

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Your error low value for the Lambda is set to 1 Volt.  This should normally be 0.05 V or sometimes might need to be 0 Volts to suppress errors on start up.

image.thumb.png.88165301377922a8cf59a0416ee1081e.png

 

Also, try the Link NTC1-8 & IAT1-8 Calibration and see if they are closer (that normally fixes the bottom end of the cal.)

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CJ, right on the money, I changed the parameters until today as I hadn't received the AEM UEGO so installed it and setted it up. 

 

On 7/18/2019 at 8:15 PM, cj said:

I think its something to do with your fuel pump control causing the pump to shut off or go into low output mode. The bit where your foot is flat, but your RPM is dropping is the key point for me. 

Can you get your wideband running so we can see if its going rich/lean while the revs drop at full throttle? Alternately, get a fuel pressure gauge/sensor installed?

Maybe try setting the fuel control cutover to something like 4k & 50% DC as a test, and if that makes no difference, try disconnecting pin aux2 from the ECU and applying straight 12v to it (which should force the pump to high throughput mode)

this is what I did the cutover and the DC crossover

and now the same thing as before happens but at 5000 rpm 

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sounds like progress. Next thing then is to figure out what FP control settings will make it behave properly. 

Try changing the polarity of aux2 to high and see if the problem get better/worse. 

can you hear the fuel pump at idle? Maybe have someone put their head in the boot and check? I'd be tempted to disconnect aux 2 from the ecu temporarily (cut the wire, un-pin it from a connector anywhere between ECU and FP controller), then at idle (so pump is running), connect it to ground, then floating, then 12v and see which connection makes the pumps jump up into high flow mode. From there you can work out what to configure in the ECU, or if you need to add a relay to deliver the right voltage.

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Thanks CJ, I find it a bit odd that it doesn't work properly from the get go but I assume it is because many used different aftermarket pumps, I just raised the crossover to 7500 and I am clear without any hiccups, but of course I am not sure what it will happen when boost is created until tested. I tried to find out what exactly does the parameters do on the help file but nothing to be found. 

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In simple terms, the FP control system is set up so that the ECU tells a separate fuel pump controller whether to run the pumps fast or slow. It does this by sending a voltage (or ground) signal down the aux2 pin when certain cirteria are met.

Relevant parameters to your situation are:

RPM threshold: the RPM at which point the signal is sent down this wire to the FP controller

DC%: injector duty percentage - works as an OR operation with RPM. If you go over this injector duty cycle or this RPM then the control voltage is sent to the controller

polarity: whether the "switch to high mode" signal is to send ground or to send "nothing" (ie the "go slower" command is to send ground).

The expected state of the FP controller are:

off (when the fuel relay is turned off - not relevant here)

slow: some pwm'd low output mode

fast full flow rate.

 

What i've been trying to explain is that you need to identify how the voltages on that FP controller input (aux 2 output) affect what the controller does with the pump speeds. It sounds like the "dont do anything" signal from the ECU as it stands is "fast mode". This will work fine if you just set both thresholds to really high numbers (10k rpm & 99%DC), but this means you dont have a "slow mode" option for low load times. It just means your pump is noisy-er and wears quicker. If you want to reconfigure this to the point where idle-ish loads swap to low flow mode, you would first need to identify what the signal is that makes it swap to high flow mode, then configure the ECU output to provide that signal. Note that some outputs can send 12v or ground, and some can only send ground or nothing.

 

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I totally understand you now, I will do the tests just as you have explained to figure out how it works even if i don't have any use for extra pump.

Thanks for your time your explanation is perfectly clear.

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CJ I forgot to write, I tried this:

Try changing the polarity of aux2 to high and see if the problem get better/worse.  The ECU got all crazy, pump instantly shut down and got checksum error and wouldn't let me revert, pump was dead, removed battery and all clear I was able to put low and save. 

I simply turned off the fuel pump control as client is nervous of me tweaking the fuel pump controller and messing something up, so for now no cuts, all good to redline.

 

 

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Ive had issues with the fuel pump control on the 2j pnp units in the past.  I usually just bypass the fuel pump controller and just change the ecu to standard fuel pump relay control.

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