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GuiTaR
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I have a 2015 that I have just added fuel pressure monitoring to. I chose the JV MAF 2 kit which connects to both the bank 2 map sensor and bank 2 maf sensor. Problem is, when installed, I get no MAF voltage (this is what tuner says is required to use the fuel pressure features) 
 
I have tried connecting the oem MAF loom into the MAF sensors and I get voltage (about 0.33v with just ignition on). Now, I'm guessing this is ok as MAF 1 and MAF 2 are identical. When I unplug them to put MAF 1 into the SD kit and MAF 2 into the fuel pressure kit, I get zero volts. Tuner says this is not right.
 
I'm wondering if any gurus on here can give me any ideas on troubleshooting...
 
What I have seen so far:
 
2 of the 3 pins at the fuel pressure plug that connects to the OEM MAF plug have 5 volts. The 3rd pin does not line up with the MAF connector pin which has 12v. I'm told this may be fine as 12v will destroy the fuel pressure sensor.
 
resistance between pins on the fuel pressure sensor itself is 4.19 ohms between one pair, 4.96 ohms between another pair, and nothing for the final pair. (can't remember which was positive, negative, and common pins).
 
Any ideas would be helpful because I know I'm annoying the tuner, trying to get this problem resolved so we can start tuning....
 
Cheers,
 

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GuiTaR
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Discussion Starter · #3 ·
I did, his responses have been few and far between, so I guess I'm pissing him off a little haha

Thought I'd just check to see if anyone on the forum has any ideas

Sent from my CPH1701 using Tapatalk

 

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Can you link a picture of the kit in question? Not sure why you would use both the MAF and MAP connectors for a fuel pressure kit. MAP connector is needed for the +5V because I believe the MAF sensor is actually +12V. If you use the MAP sensor +5V then you would also use the MAP sensor signal pin to feed the fuel pressure sensor output back to the ECU. Therefore, no need to tie into the MAF connector. I have made a few of these kits so it should be very easy to troubleshoot.
 

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GuiTaR
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Discussion Starter · #5 ·
Not gonna lie, I was hoping you might respond. I'll get a picture asap and post it here.

I believe the maf is used to keep the map sensor functional. Regardless of sd tune, my intention was to keep as many things functioning as normal as I could. Most of this is a little above my head, however. I can do mechanical... Electrical... Well...

Until I get a pic of the loom, I've attached pics of the data sheet for the Honeywell sensor. Let me know if you see anything that might suggest incompatibility...
5d642ca0616585a2fd5a57f281570ca8.jpg
91e1f40842cf37ab44fa86ee777c28a7.jpg


Sent from my CPH1701 using Tapatalk
 

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Not gonna lie, I was hoping you might respond. I'll get a picture asap and post it here. I believe the maf is used to keep the map sensor functional. Regardless of sd tune, my intention was to keep as many things functioning as normal as I could. Most of this is a little above my head, however. I can do mechanical... Electrical... Well... Until I get a pic of the loom, I've attached pics of the data sheet for the Honeywell sensor. Let me know if you see anything that might suggest incompatibility... Sent from my CPH1701 using Tapatalk
You can always PM if you need something. Also post what SD kit you are using. Typically, the SD kit uses a dual pressure/temperature sensor to replace the OEM pressure sensor. This dual sensor allows for temperature measurement pre throttle body so the ECU can approximate air density. The pressure signal is fed to the factory MAP connector and the temperature signal is then fed to the passenger side MAF connector. If you have this type of SD kit then the passenger MAF and MAP connector signal pins are already being used. Just show me what you have in terms of the SD kit and the FP kit.
 

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Visconti has several kits. The MAF one with SD would use 1 wire of the MAF temperature signal to feed the new integrated MAP sensor, the MAF has a separate input for the frequency part of the MAF, so you should be able to use one MAF harness to connect both Temp from MAP and Fuel pressure signal, they would just use different wires.

Also I just checked the diagram, the MAF Bank 2 only has 1 input, it has no temp signal. So you can't use MAF 2 plug for both fuel pressure and Temperature.

Here is the diagram.

only Bank 1, can be used for both temp and fuel pressure signal.

I also checked visconti website, he does not sell a combined SD + Fuel pressure kit for Bank 2. So if you have one that is combined, it is for Bank 1 and that is why it doesn't work.

KCkjEY.jpg
 

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GuiTaR
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432 Posts
Discussion Starter · #8 ·
I bought the SD kit previously. Then I bought this maf 2 fuel pressure kit which states it is specifically for vehicles with sd kits already installed...

MAF BANK 2 KIT

EcuTek Only

Perfect for those who already have an existing Speed Density Kit.

  • Plug & Play
  • Interfaces with the ECU via BANK 2 MAF sensor input
  • Not COBB compatible

I'm hoping there aren't any issues with using this kit on my setup. You'll have to pardon my ignorance relating to wiring, but my understanding was that they get power from MAF2 but signal wire from MAP2...

Does that make sense, or am I on the wrong track here?
 

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I bought the SD kit previously. Then I bought this maf 2 fuel pressure kit which states it is specifically for vehicles with sd kits already installed...

MAF BANK 2 KIT

EcuTek Only

Perfect for those who already have an existing Speed Density Kit.

  • Plug & Play
  • Interfaces with the ECU via BANK 2 MAF sensor input
  • Not COBB compatible

I'm hoping there aren't any issues with using this kit on my setup. You'll have to pardon my ignorance relating to wiring, but my understanding was that they get power from MAF2 but signal wire from MAP2...

Does that make sense, or am I on the wrong track here?
Perfect. Just take the passenger side SD kit out of the equation because it should have no bearing on your issue. Please remove the Fuel Pressure Kit (MAF Bank 2) and take a picture of it on the ground so I can see all of the connectors.

The fuel pressure sensor requires +5V to generate the output signal, which is pulled from the MAP sensor connector since the MAF connector (MAF sensor) operates on +12V. So basically, the kit pulls the +5V signal from the MAP connector and feeds it to the fuel pressure sensor. The 0-5V output signal from the fuel pressure sensor is then fed to the signal pin on the MAF connector.

With the kit installed and the car on or in ACC mode, unplug the connector from the fuel pressure sensor and verify one of the pins is showing +5V. It is typically a red/white wire, but you can reference the sensor wiring from the link below, but basically one of the pins on the connector will show +5V.

https://www.powertraincontrolsolutions.com/download/Released/Public//Manuals/Pressure_Sensor_User_Guide.pdf
 

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GuiTaR
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Discussion Starter · #10 ·
I'll take a full pic of the loom for you ASAP.

Should I remove the SD kit prior to testing voltage at the Fuel Pressure Sensor plug? What kind of bearing would this have on the result?

I will confirm voltage before I reply again, however, I did test that before, with ignition on, I got 4.96 volts at the Fuel Pressure Sensor plug which is why I'm perplexed... Should I do it with just ACC on?

Perfect. Just take the passenger side SD kit out of the equation because it should have no bearing on your issue. Please remove the Fuel Pressure Kit (MAF Bank 2) and take a picture of it on the ground so I can see all of the connectors.

The fuel pressure sensor requires +5V to generate the output signal, which is pulled from the MAP sensor connector since the MAF connector (MAF sensor) operates on +12V. So basically, the kit pulls the +5V signal from the MAP connector and feeds it to the fuel pressure sensor. The 0-5V output signal from the fuel pressure sensor is then fed to the signal pin on the MAF connector.

With the kit installed and the car on or in ACC mode, unplug the connector from the fuel pressure sensor and verify one of the pins is showing +5V. It is typically a red/white wire, but you can reference the sensor wiring from the link below, but basically one of the pins on the connector will show +5V.

https://www.powertraincontrolsolutions.com/download/Released/Public//Manuals/Pressure_Sensor_User_Guide.pdf
 

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GuiTaR
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432 Posts
To add, looking at your attached diagram, and comparing to the diagram of my sensor, the pin locations appear to differ. Does it look like I just need to swap around the order of the pins in the connector for the fuel pressure sensor?
d65da9c979c183903c461776d40ffad9.jpg
81eb4b296ceea7391aa1016035575c1e.jpg
Sent from my CPH1701 using Tapatalk

Edit**** Scratch that, it's late here. Turns out it looks to match up.
 

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I'll take a full pic of the loom for you ASAP.

Should I remove the SD kit prior to testing voltage at the Fuel Pressure Sensor plug? What kind of bearing would this have on the result?

I will confirm voltage before I reply again, however, I did test that before, with ignition on, I got 4.96 volts at the Fuel Pressure Sensor plug which is why I'm perplexed... Should I do it with just ACC on?
The SD kit on the passenger side of the motor using the MAP and MAF connectors will have no bearing on the fuel pressure kit since the fuel pressure kit plugs into the driver's side MAF and MAP connectors. The engine should not need to be running so push the red button twice without your foot on the break and that should power the sensor. Just confirm you have +5V to the fuel pressure sensor connector. You said this test was previously performed and it showed 4.96V so please repeat to verify.

If you see 4.96V at the fuel pressure sensor connector then plug it back into the fuel pressure sensor. Then disconnect the driver's side MAF connector because that is where the output signal from the fuel pressure sensor will feed into the ECU. Start the car and measure the voltage you are seeing at the MAF connector and let me know. Best to do this with the car running because we know approximately what the fuel pressure should be (assumed stock FPR) and we can then correlate that to a voltage since the sensor response from the Honeywell sensors are linear, [email protected] and [email protected]

If you are getting a good signal at the MAF connector then likely just your tuner not turning on the function in ECUTEK allowing the driver's side MAF connector to be used as a fuel pressure input.
 

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GuiTaR
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432 Posts
The SD kit on the passenger side of the motor using the MAP and MAF connectors will have no bearing on the fuel pressure kit since the fuel pressure kit plugs into the driver's side MAF and MAP connectors. The engine should not need to be running so push the red button twice without your foot on the break and that should power the sensor. Just confirm you have +5V to the fuel pressure sensor connector. You said this test was previously performed and it showed 4.96V so please repeat to verify.

If you see 4.96V at the fuel pressure sensor connector then plug it back into the fuel pressure sensor. Then disconnect the driver's side MAF connector because that is where the output signal from the fuel pressure sensor will feed into the ECU. Start the car and measure the voltage you are seeing at the MAF connector and let me know. Best to do this with the car running because we know approximately what the fuel pressure should be (assumed stock FPR) and we can then correlate that to a voltage since the sensor response from the Honeywell sensors are linear, [email protected] and [email protected]

If you are getting a good signal at the MAF connector then likely just your tuner not turning on the function in ECUTEK allowing the driver's side MAF connector to be used as a fuel pressure input.
Hey mate,

So, still yet to perform the above tests due to time constraints. I did, however, come across this little paragraph relating to my particular sensor...

This model runs on a supply voltage of 9.5-35Vdc to provide an output signal of 4-20mA. If required, this can be converted to a 2-10V signal by using a 500ohm resistor across the signal output. Since 500ohm resistors are not readily available, a 500ohm resistance can be configured by using 2 x 1kohm 0.5Watt resistors wired in parallel with each other across the Common and Output terminals of the sensor, these are provided with each sensor and can be wired in at the input to the controller/ECU end. The ST transducer delivers±1.0% full scale accuracy (BFSL) over a wide temperature range of -40° to 100°C and utilises a proven industry standard connector for high reliability.

That sounds like I need to wire in these resistors, correct?

Or time for a different sensor? This is a 100psi sensor BTW
 

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GuiTaR
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Discussion Starter · #15 ·
Sounds like wrong sensor if it uses 12V input. I would not mess with resistors and get the correct sensor for the application. Did you buy this sensor separately?
Yeah, I'm thinking along the same lines as you. I bought a 100psi sensor as the JV kit comes with 150psi and I wanted maximum resolution.

I'll get another sensor and report back...
 

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Yeah, I'm thinking along the same lines as you. I bought a 100psi sensor as the JV kit comes with 150psi and I wanted maximum resolution.

I'll get another sensor and report back...
If you ordered the ST100PG1SPGF, that is not the correct sensor. Order this sensor (Honeywell Part # MLH100PGB06A) from my buddy's company below, which is the high temp version of the sensor you want and is exactly what I run. I verified with him it is indeed Honeywell Part # MLH100PGB06A.

https://www.powertraincontrolsolutions.com/Performance_Aftermarket/Products/Sensors/Pressure_Sensors/A-SNS1003/
 

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GuiTaR
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432 Posts
Discussion Starter · #17 ·
If you ordered the ST100PG1SPGF, that is not the correct sensor. Order this sensor (Honeywell Part # MLH100PGB06A) from my buddy's company below, which is the high temp version of the sensor you want and is exactly what I run. I verified with him it is indeed Honeywell Part # MLH100PGB06A.

https://www.powertraincontrolsolutions.com/Performance_Aftermarket/Products/Sensors/Pressure_Sensors/A-SNS1003/
Does your buddy have a direct contact for me to purchase from Australia? I've emailed the Aussie distributor, however, just in case it's an issue for them....
 

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Does your buddy have a direct contact for me to purchase from Australia? I've emailed the Aussie distributor, however, just in case it's an issue for them....
If their Australia rep can't get it, just use the part number I gave you and see if you can source independently. If that fails we can discuss via PM.
 

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GuiTaR
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432 Posts
Discussion Starter · #19 ·
Just to put this to bed, I got the sensor recommended by 240 and all is working correctly, now. Thank you, everyone, for your assistance with this. :)
 
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