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[berserkerboy]

Last chance for the old girl.

I have been having problems starting the car on petrol but can hard start on gas. I have tested the purple relays which both seem to be working fine. Ie. continuity across the small spades and good closure on supplying 12v to create continuity across the large spades.
I have fitted a new fuel pump as RAC told me that was the issue. However, the car still refuses to start.
I have disconnected at fuel feed manifold, I am assuming the right hand larger pipe is the feed? On crank over no petrol is coming out. The voltage at the pump is about 9.5v on crank over. Is this correct? If so then i guess the new pump is faulty?

[Doctor Gollum]

You should have 12 v at the pump

[berserkerboy]

When the ignition was first turned on I had 12v briefly which then reduced to zero. When I was cranking over voltage went back up to 9.5v and remained there whilst cranking. I wondered if this was due to the demand on the battery. Would 9.5v be enough to get some pumping of fuel?
I think I'll remove pump and see if a 12v supply runs it.

[zirk]

When Cranking, the Battery voltage call fall considerably, roughly anything above 9.7 when cranking is the threshold between a good and bad battery (assumes accurate Voltmeter),

Whats the Battery Voltage (measured at the Battery) when cranking?

[berserkerboy]

Well, I've been charging the battery as I've been cranking it over for a while. Just checked the voltage at the battery whilst cranking: 10.66v. Same at the pump which would suggest faulty new pump?

[Doctor Gollum]

Well, I've been charging the battery as I've been cranking it over for a while. Just checked the voltage at the battery whilst cranking: 10.66v. Same at the pump which would suggest faulty new pump?

No, the pump won't run until the crank sensor agrees that the engine has fired.

[berserkerboy]

Surely the engine needs pumped fuel in order to fire? Seems a catch 22.
Shall I run a 12v from the battery to the pump to see if it's working?

[Doctor Gollum]

Surely the engine needs pumped fuel in order to fire? Seems a catch 22.
Shall I run a 12v from the battery to the pump to see if it's working?

Ignition on, pump runs to prime the fuel rail... Injectors and fuel rail hold enough fuel to idle the engine for 5-10 seconds, by which time the damn thing should be running without the starter. Pump then kicks in and runs until you switch the ignition off or the crank sensor dies... Whichever comes first.

[zirk]

Surely the engine needs pumped fuel in order to fire? Seems a catch 22.
Shall I run a 12v from the battery to the pump to see if it's working?

Pump gets primed when Ing. key on, can normally here it and relay clicking.

Cant remember if you can pull the Cover off the relay and and force the contact so the pump runs on a 3.2 ?, I know you can on a 3.0.

[berserkerboy]

Just jacked a 12v supply and earth into the plug. Ensured continuity. No sound from the pump. Gonna whip it out to see if it's faulty.

[Doctor Gollum]

Just jacked a 12v supply and earth into the plug. Ensured continuity. No sound from the pump. Gonna whip it out to see if it's faulty.

Plug on top of tank?

[zirk]

Ive only just seen the word LPG in your Profile, 

Sounds like youve burnt the petrol pump out by running the tank low when running on Gas. 

[berserkerboy]

Pump is fine. Just couldn't hear it. Yes plug on top of tank. Should have disconnected the fuel manifold again to see if it was priming.
Thanks for your help guys. Can't spend any more time or money on this car. Struggling to start on gas now. Probably too low voltage on crank.

If the crank sensor was faulty it wouldn't have run on gas would it?

[Doctor Gollum]

Possibly as that only switches off the fuel pump at cranking... Injectors are powered as they are needed for normal firing.

Pull all the spark plugs along with fuse 18.
Crank engine for 15 seconds.
Wait ten minutes.
Crank engine for 15 seconds.
Pour a tablespoon or two of oil down each plug hole.
Wait ten minutes.
Crank engine for ten seconds.
Fit new plugs and reconnect everything including the fuse.
Now try and start the car.

A quid bets ten that it starts within five attempts 

[terry paget]

Surely the engine needs pumped fuel in order to fire? Seems a catch 22.
Shall I run a 12v from the battery to the pump to see if it's working?

Ignition on, pump runs to prime the fuel rail... Injectors and fuel rail hold enough fuel to idle the engine for 5-10 seconds, by which time the damn thing should be running without the starter. Pump then kicks in and runs until you switch the ignition off or the crank sensor dies... Whichever comes first.

Not on my 2.5. As described 28Feb2017 http://www.omegaowners.com/forum/index.php?topic=138599.0 my 2.5 needed 2 long starter squirts to start the engine. I eventually traced the fault to an earlier pump change using jubilee clips, which I replaced with spring clips, curing the fault. In my book, the fuel pump gets 12 volts when ignition is on, crank sensor is pulsing, or starter is cranking.