16v Bigport fuel problems

[Rascal21]

Hi all

I`m having a problem with my 16v Bigport, namely no fuel pressure in return line with fuel pump on.

Before this I`ve excluded ignition issues, swapped coil and igniter twice just for fun, swapped cold start injector, and I know fuel in and ex line is not clogged, spark plugs wet.


To be sure I disconnected the fuel return hose coming from the intake and into the return line, and put that hose into a battle, ignition on, fuel pump on, no fuel returns..

Could this be fuel pump not giving enough pressure or injectors always open?
Engine reeking of fuel after a bit of trying to start it, ignition on with fuel pump etc etc.

Now and then I can start it without ever finding out what the problem is, and when it does start it revs fine, runs rich but no misfire, but will only work for 50 seconds, bog down once, come back up, another 10 seconds of engine running, then stall.
Mostly cannot start it at all.

I also have a thread on aeu86 where all other issues like ECU error codes, TPS, Igniter, Coil, Battery, Injectors getting power, Coil getting power, ECU getting power, Alternator and every other little tid-nit has been checking out fine.
What I have not checked is injectors, because they are sitting like way down in there and no idea how to get the metal clip harness connectors off :v

She cranks, fuel pumps work, but mostly wont start and as I mentioned when she does start will only work for about a minute before stalling out again.

[jondee86]

Facts...
- pump is running.
- engine is getting fuel, but most times does not run.
- engine runs sometimes, but rich.
- after crank and no start plugs are wet.
- no fuel returning to tank.

Probable cause...
- fuel pressure regulator is blocked/stuck closed.

Theory...
- a blocked FPR will cause rail pressure to reach 70psi or higher.
- high rail pressure will cause the engine to run extremely rich.
- mixture richer than around 8:1AFR will not burn.

Conclusion...
- starting mixture is too rich and engine floods.

Action required...
- replace FPR.
- install fresh spark plugs.

Let me know how you get on

Cheers... jondee86