1.3 MultiJet - resistor in rail sensor

[Danielski]

Hello
I want to slightly increase the power in my Fiat 1.3 MultiJet, I was thinking about the resistor / potentiometer on the fuel rail pressure sensor (3 pins, one is 5V), but I do not know which pins to use. I have a multimeter. Must the connection be serial or parallel? If parallel, between which pins? Thank you very much in advance

 

[BLACK'98DSM]

Welcome to the forums! I'm not exactly sure how you came to DSM forums with a Fiat , but you are welcomed anyway!

Can you post a picture of the connector for us to see?

 

[Danielski]

I've been digging the internet for several days to find out something, I thought that this place a good choice Sensor has 3 pins, one is 5V, it looks like this https://www.aliexpress.com/item/32796933537.html

 

[1990TSIAWDTALON]

One will be ground, one will have 5V+ with the key on and the 3rd terminal is the sensor feed back to the ecu. Don't know which is which, do you have the plug on your car that this sensor can plug directly into or are you having to wire it up all on your own?
Welcome to the forum, we try to help all!

 

[Danielski]

i will wire it up on my own. So i can cut signal wire and put resistor in serial? Or maybe it should be in parallel with ground/5V?

 

[1990TSIAWDTALON]

Are you trying to "trick" your ecu? Is that what the resistor is for? I assume that the sensor itself will need a 5V+ source, maybe in your engine bay for a MAF or other sensor. It MAY also need to use a sensor GROUND but you can try a chassis ground to start, then the sensor should return a value in the signal wire to your ECU. Some sensors have to use an ECU sensor ground instead of chassis ground, so be aware of that.
Tell us what you are trying to do, we can possibly be more help that way!
Marty

 

[Danielski]

Are you trying to "trick" your ecu?

Exactly. I want to add more fuel, maybe more boost in future depending on results. I will operate on actual sensors in car (rail fuel pressure sensor and maybe boost sensor, but focus on first as i linked). I prepared potentiometer 0-2kOhm with long wires to check best resistance and use simple resistor under hood, but first i must know where i should plug this. I don't want to cut all wires so im asking. In my opinion, just plug resistor serial on signal cable, but on pictures in network (eg opened chip boxes) i see parallel connections (between signal and ground? I don't know)

 

[1990TSIAWDTALON]

Man, can you throw a link to what you are attempting to do?
I would assume, like you, that it would be in series with the signal wire but I'd have to see what wiring diagrams you are referring to in order to make any more suggestions.
The variable potentiometer is a good tool for finding what value you are going to end up with.

 

[Danielski]

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something like this shit plugged in to fuel rail pressure sensor or boost sensor (i also found similar modifications at MAF sensor, but there it was in serial connection...).

 

[1990TSIAWDTALON]

Do you thing that resistor is on the signal line and then tied over to ground or 5V? I see whats going on. You will use a potentiomenter in that spot until you decide the value that works best for you, like a volume control from an old radio or such? I have to say I am not familiar with FIAT hacks like DSM hacks, so you may have to explain more, but we can discuss it no matter what.