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ST170 fuel pressure switch
Johnny B - 1/6/22 at 09:49 AM

Hi, I`m missing the fuel rail pressure switch for my ST170 race engine.
Is there anyone who knows where i can get one of these?
I have found several on ebay, but they are not compatible with the ST engine. Is it possible to use one from another engine, and in that case, which one?
My problem is to get fuel trough the injectors, and I suppose the problem will be solved if I connect the pressure switch to give signal to the ECU. The fuel rail are wrong (not original), with the return line back to the fuel tank, so i will reduce the flow trough this as well.

Regards Johnny B (Norway)


big_wasa - 1/6/22 at 10:39 AM

Its not that simple on the St170. The pump has a seperate driver that is triggered by Pwm from the factory ecu.
Not an on/off like the zetec.


Johnny B - 1/6/22 at 02:58 PM

So it wont work with a non standard fuel pump directly connected to an on/off switch?
I thought the ECU just needed a signal from the switch that there are fuel pressure, and the injectors would get power from the ECU.

Regards Johnny B


big_wasa - 1/6/22 at 09:27 PM

The driver will drive a non standard pump but I can’t tell you how the ecu will like no input or response from the missing equipment.


big_wasa - 1/6/22 at 09:28 PM

https://youtu.be/gjsu8mMp0kw


djtom - 8/6/22 at 02:34 PM

I've got a fuel rail complete with the pressure sensor from a ST170 if you need it. No injectors, just the rail and sensor, which was working fine when removed from the donor vehicle. Drop me a U2U if you are interested, I'm after £25 plus postage.