Fuel Pump on the way out?

[Phoenixx]

Ever since I have owned my VR Stato 5 Litre dual fuel there has been this persistent knock in the motor but only when running on petrol. My mechanic stuck his head under the bonnet and said it's the injectors and felt the fuel hoses and they were "pulsing" in his words. We went to the back of the car and there was this high whining buzzing whirring fizzing type sound and he said that was the fuel pump sounding like it might be on it's last legs. I also get an intermittent strong fuel smell which seems to be coming from under the car and the engine bay but have never found any signs of fuel leakage on the ground. I also have an intermittent exhaust smell inside the car when the windows are down but this goes when the windows are closed again.
So could a bad fuel pump be causing the pulsing in the fuel lines, the noise of the injectors and the fuel smell maybe and also can any or all of these symptoms be caused or contributed to by a leaking exhaust gasket? The car idles smooth and runs fine under load with no miss or hesitations in the motor, just the constant injectors noise. As soon as I flick it onto gas the noise stops by the way.

[Robbo VS3]

The exact same problem was happening to me mate, the whining sound and the smell of fuel. I put in a brand new fuel pump. Problem solved.

[Phoenixx]

Cool, thanks mate, always good to get a second opinion. Were you having any problems with your injectors while your old fuel pump was dodgy?

[Robbo VS3]

No i did'nt have any problems at all with the injectors.

[Sharpie]

the pulsing of the fuel line is normal and injectors "ticking" while running on petrol is normal. I had a real bad fuel smell from my old vp and found all the breather lines on the fuel tank worn and holed.

[99VSIIIUte]

Hi mate,

I bought a 99 VS Ute around 4 months ago and same thing happened with mine BUT - the fuel filter kept getting clogged up at first - went through 2 fuel filters and broke down twice before I bit the bullet and took it to the mechanic.

He thought I had a stuffed/rusted out fuel tank so bought one from the wreckers and tidied it up - turned out my tank was fine and it was the fuel pump all along and I used to get that smell of fuel alot too. Mechanic checked my injectors too and they were spot on. Ive also kept running Premium in my car since its had work done it.

Intrestingly enough my Ute used to have gas on it and was pulled off and removed by the previous owner....wonder if that has anything to do with it???

[LeeoD]

The problem with the fuel pump is its not on a pendulum so it does not swing in the direction of gravity. It's in a fixed position bolted to the bottom of the tank. When you get to the 1/4 full mark on your gauge and lower, you can starve the fuel pump of fuel. This causes the pump to run dry momentarily when going up and down steep hills and around tight bends. The fuel pump uses the fuel to cool it. It can overheat quite a bit if you keep on running it below 1/4 of a tank of fuel in it and cause a failure. The pump is pretty robust and can handle low fuel levels for quite some time but after about 250,000k's they start to give up and die all of a sudden without warning. If you can afford it, try and keep your tank between 1/4 and 1/2 full at all times and prolong the life of your fuel pump.

[Phoenixx]

Thanks for the great replies from all, much appreciated...