Fuel Pressure Goes To Zero When Car Starts

[2JZNA-T]

Hey everyone, finally have my emu hooked up. Got it to get the car started. When i turn the key in the on position i can hear my fuel pump turn on and pressurize the fuel system.

Soon as the car starts the fuel pressure will drop all the way to zero and idle very low.

If i try to give it any throttle it just dies.

Im wondering why on earth my fuel pressure would suddenly drop when the car starts ? I turned my fuel injector trim down 50% as it was on a 100% and causing it to run extremely rich.

So now im wondering what could cause the fuel pressure to drop so low AFTER it starts ?

I know there is nothing wrong with my FPR or fuel pump. So i don't understand it.

Ideas ?

Thanks

[WHPZach]

Try inverting the signal for the fuel pump. It's in the "outputs" menu.

[2JZNA-T]

Ok that seemed to work, then about a minute after the program suddenly is reading " DISCONNECTED " i turned off my ignition then turned it back on and it won't connect ?

[Jadzwin]

Is your EMU detected (as USB device) by your PC after power up ?

[2JZNA-T]

Nothing seems to be detected what so ever.

I was told to try and connect it via USB again, turn on the key and try to click firmware upgrade and it just says " cannot enter boot loader "

I've used two laptops with the latest program, uninstalled the programs on both then re installed them with the driver and made sure my laptop was not plugged into the charger.

No matter what it just shows the disconnected sign when the key is on or off. Doesn't seem to make a difference.

What i noticed leading up to this sudden problem is right before i was trying to invert the fuel pump signal is it was working perfectly.

After i inverted the fuel pump signal it seemed to work for 5-10 seconds and i was able to keep the car running with my foot slightly on the gas peddle.

Then suddenly the car died and and key was still in the on position and the emu was reading disconnected. After that, its never been able to connect again.

[Jadzwin]

What did you connect to stepper outputs ?

[2JZNA-T]

I bought it as a plug n play emu for the 2jz ge supra. They wired it specifically for my application.

They just recommended to take the emu out of the car, and take some of the extra wires included. connect pin 18 on the grey connector to the pos of the battery and 17 of the black connector to the ground of the battery and see if the computer works then. But still the " flashing red disconnected sign on my lap top still is there.

Im completely unsure now.

[Jadzwin]

Looks like device is broken...

[2JZNA-T]

How do i go about it then ?

[Jadzwin]

Please contact your dealer first. The device is under warranty.

[WHPZach]

Problem resolved. The EMU wasn't faulty, it was a USB driver issue. After he reinstalled the USB driver it worked well.

[2JZNA-T]

Sadly im having the problem again. Before i got it to connect, and soon as it worked i closed the program and disconnected the power and installed it the next day. Same problem.

So i took it back out, connected it to the battery and its not seeing the USB connection.

I re installed the driver once again today and for some reason it happened again. Yet this time even when i follow my steps that i did last time its not making a difference.

If there is any tips it would be greatly appreciated.

I also even borrowed a friends computer and installed the software to the computer and have the same results.

any info would be appreciated !!!

[Kisielisodd]

Using multimeter check continuity between pin G18 sensor groung / G17ecu ground, and USB metal housing. If there is no contiuity there is your problem.

[Jadzwin]

Please try to download the latest USB drivers:

http://www.ftdichip.com/Drivers/CDM/CDM ... tified.exe

[2JZNA-T]

I thought G18 was 12 v pos and B17 was ECU ground ?

Im going with this pin out.



Or do you mean check between G18 and B 18 ?

Sort of confused

[Kisielisodd]

My mistake, B17/18

[2JZNA-T]

Checked the continuity between B 17 and G 18 and no signal.

They are telling me that its most likely my computer thats making the error.

I also checked the voltage on my harness for G 18 and B 17 and im geting my full 12.5 volts to the emu. Still no luck.

Car has been sitting for awhile and i just need to get it running.


When i turn the key on i can hear the fuel pump going. but i have no connectivity.

[Jadzwin]

Maybe the porblem is faulty USB cable ???

[2JZNA-T]

I already had purchased another cable. and had the same result.

I just mailed it back to the seller.

really hoping i can figure something out here. I've already used the program on 3 different laptops and still have the same result.

Also i checked the continuity between G18 and B 17 and there is no continuity between those pins.

My craftsmen multimeter has the beep function that will create an audible beep to know if there is any continuity what so ever and it didn't beep or have any reading. Which to me says there is some connection that is not secure with in the EMU.

However i may be wrong.

Its just the frustration i've been going through is too much. I've done just about every test possible that has been requested and i've not had my issue fully resolved.

At first i thought it was sorted out the other day but for some reason it once again will not connected to my laptops.

[Angelo S38]

I think you should check continuity beween B17 B18 and the USB