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Now i know the general consensus is that FPR's are not needed even for 300rwkw there abouts, provided with the correct injectors and fuel pumps. But what if the fuel pressure is low at idle, say 2 bar? Is it enough to justify that an FPR is needed?

Basically, my setup is

PFC, stock injectors, sard 280 lph fuel pump, pods and exhaust.

During the tune, fuel pressure is low at idle, showing 2 bar, hence my tuner said thats the cause of the sudden spike in afr's towards the 7k rpm during a tune done earlier. Have replaced a fuel pump since, without increasing the voltage, although i have suggested that to my tuner, but he said its not necessary.

Given that scenario, should i get an FPR? Planning to get a sard FPR.

Opinions ?

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Have you checked your fuel pressure after the pump was replaced? If you have and it's still low you could check the voltage at the pump and make sure that is what it should be. If it's low then up the voltage. There is a few great tutorials on how to do this. After you have done all if this then maybe look into a fuel pressure reg. Have you changed your fuel filter lately?

Have you checked your fuel pressure after the pump was replaced? If you have and it's still low you could check the voltage at the pump and make sure that is what it should be. If it's low then up the voltage. There is a few great tutorials on how to do this. After you have done all if this then maybe look into a fuel pressure reg. Have you changed your fuel filter lately?

After the pump is replaced, i asked the tuner again and again if voltage is enough, he confirms its enough without rewiring or increasing. Yeap, i have changed the fuel filter.

Basically, the tuner said after installing the pump, if my stereo works fine, volt is supposedly sufficient. :S

what does the stereo have to do with it?

What a monkey - go find another tuner.

You measure the pump volts from the boot, and only the boot where the pump is located.

Changing the pump DEMANDS that you rewire. A/M pumps need MORE power.

is he measuring pressure properly? with or without vacuum? at idle the reg is under vacuum. you need to subtract or add boost or vacuum from the reading. easiest way to do that is disconnect the vac line to the reg then test the pressure at idle.

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