16v 1.4 Kseries multipoint injection

[sinky]

Can anyone tell me if the fuel tank fitted to the single point injection engine is the same as the multipoint version. I have a problem with fuel pressure and the only way I can get the engine to work is to restrict the flow to the injector rail by the means of a clip. If I take it off the engine will idle but stall when put under load.
Any ideas

[Mr2Mike]

If you really are restricting the flow to the fuel rail, then that would imply the engine is running too rich under load. The fuel pump is unlikely to be the culprit as the fuel pressure is determined by the regulator which returns fuel to the tank. Hence, within limits, fuel rail pressure is independant of flow. One possibility is that the fuel return pipe has been kinked, or the fuel pressure regualtor has somehow jammed shut (not a common failure mode IME).

If OTOH you are actually clamping the return from the regulator and hence increasing fuel rail pressure, this would be consistent with the engine running weak under load. Typical causes would be a faulty fuel pressure regualtor, leaking or blocked MAP sensor pipe (the one that goes from the inlet manifold to the MEMs ECU), blocked injectors, faulty ECU etc.

[chrisx666]

The mutipoint cars had the same tank but fitted with a higher pressure pump (about 3 times more if I remember right). The pre '100' MPI Metros had a 'banjo' type fitting on the pump, while the SPI ones just had a push on pipe. It's not easy to tell the difference on later cars as they stopped using the banjo fitting on either from some point.
I think it would run pretty bad with the wrong pump..

[Mr2Mike]

If the SPi pump runs at a much lower pressure, it dosen't explain why restriting the fuel to the injector makes the engine run better?

[chrisx666]

I know!. Just trying to answer a 'is the pump different' question with a simple 'yes they are - I suggest using the correct pump' reply.

[sinky]

Thanks for the info guys keep it commin!

[Busa_Rush]

Could be a faulty fuel pressure regulator, maybe it's not regulating properly/at all so making it run rich ?