23 replies to this topic

[Cian 'the pain' MPI]

Anyone had any issues with thier fuel pump??? Ive just put the SC 5 port system in mine and the tuners said the pressure is too low from the pump, would the pump be on its last legs? The pump is probably the original its a 99 car with 73k

[R1minimagic]

What pressure is it giving? Should be around 3bar....

[Manuel B]

MPI pump = 14.5 to 18.85 psi. part # WFX100810

How old is your fuel fiter ?, tank sock clogged ?, did they put a pressure gauge in the fuel line or guess ?. I'd start checking the cheapest fix.

[Sprocket]

MPI pump = 14.5 to 18.85 psi. part # WFX100810

How old is your fuel fiter ?, tank sock clogged ?, did they put a pressure gauge in the fuel line or guess ?. I'd start checking the cheapest fix.

Don't know where you get that information, but the fuel pressure regulator on the MPi is a 3 bar regulator.

[Sprocket]

Anyone had any issues with thier fuel pump??? Ive just put the SC 5 port system in mine and the tuners said the pressure is too low from the pump, would the pump be on its last legs? The pump is probably the original its a 99 car with 73k

the pump is not what regulates the pressure, its the fuel pressure regulator.

From memory the SC kit uss a nasty regulator with a built in guage. This will need adjusting. I would personally bin that off and buy a decent reliable fixed pressure regulator such as the 3 bar unit from Webcon.

Granted if the pump is not working correctly you won't get decent pressure, but also consider how the fuel system has been plumbed as this can also give you similar issues. remember that if the pump is working correctly, it is the pressure regulator that controls the fuel pressure, not the pump.

[Cian 'the pain' MPI]

Hi the feed from the regulator was fine at 3 bar but the feed from the pump was way to low, it would start and idle but not much else, he had to screw the regulator to the max to get it reading 3 bar

[Sprocket]

there should be 3bar between the pump, the fuel rail and the regulator. the return to the tank from the regulator will have little or no pressure.

If there is little pressure between the pump and the regulator, how can you have a higher pressure after the regulator?

either there is some confusion with how it should work, it's plumbed in incorrectly, or there is a fault with the regulator. Is it possible the regulator has been plumbed in back to front?

If you are still using the original MPi fuel flow and return lines, the regulator should be plumbed in after the fuel rail in the return line, with the pump feeding the fuel rail on the flow line.

Edited by Sprocket, 27 January 2012 - 10:54 PM.

[Cian 'the pain' MPI]

HI yes the regulator is plumbed in right, i would be surprised if the regulator was at fault as it is brand new. Could you please explain the last bit sprocket.

This is how it is plumbed currently

Attached Files

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Edited by Cian 'the pain' MPI, 28 January 2012 - 03:47 PM.

[Manuel B]

Page 1 in the general data/fuel system section of the Rover MPI/SPI factory workshop manual 5th edition,
fuel pump maximum pressure = 2.7 bar
regulated injection pressure = 1 to 3 bar

[icklemini]

fuel filter changed recently??

[Cian 'the pain' MPI]

would have been changed 2 mayb 3 years ago

[icklemini]

should be ok... but for the cost, it might be worth replacing it thus ruling out any blockages in the filter restricting the fuel.....

[Cian 'the pain' MPI]

Yeah might just do that! Its the things you dont account for that are the most annoying.

[icklemini]

got a fuel pressure tester? - check the fuel pressure from the tank (pump) whilst under there doing the filter....

[Cian 'the pain' MPI]

The guys at the tuning shop said the pressure from the pump was way to low