Recirculation gear on 7mgte.

[TheStitt]

The BOV or bypass valve does require a reference pressure from the inlet manifold.

So in a word yes you have to run a vac line from the BOV/bypass valve to the inlet manifold.

[kemicalx]

ahhhh, as it's the vacuum in the plenum that pulls open the piston in the valve. I've always been under the impression it was the pressure built up before the throttle body that pushes the piston back. In that case i'll try and re-route a vacuum line some other way than over the 3000 pipe so i can ditch the unused ISCV hard line.

[kemicalx]

Sorry to bring this up again guys, but i still don't follow what the VSV connected to the fuel pressue reg and the manifold pressure does.

I'm guessing at some varible, ie. tempreture, altitude, etc. the ecu signals the VSV to swtich, and the pressure from the intake is either closed off (and the vsv vents to atmosphere) or opens up, and this makes the FPR increases or decreases pressure.

If anyone knows what exactly it is doing and what causes the change i'll know if i can ditch it. having looked over the workshop manual I can't find it explained anywhere. It's not actually EGR related as i first thought. This motor doesn't have any of the EGR stuff by the looks of things.

One other thing, has anyone here removed the standard FPR in the past? If so can you remember how many washers/O-rings were on it? I thought it was a single washer on top of an O-ring. However when i screw the FPR back into the fuel rail it doesn't tighten up until it is passed the positon where it is suposed to sit. If the washer was fatter i think it would solve the problem, but as far as i'm aware it's the washer that was on there in the first place.

Thanks again guys,
Any help will be greatly appreciated

[3sgte]

The VSV connected to the fuel pressure regulator is used for "fuel pressure up" at idle and light loads after a hot restart.
It helps to avoid the fuel boiling in the fuel rail after a heat soak.

If you are running a standalone ECU, then just ditch it and connect the FPR vacuum hose direct to the intake manifold.

[kemicalx]

cheers mate, thats what i was hoping to hear