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homeless · 12-12-2017, 02:53 PM

Always starts right up with just a simple turn of the key. But lately I been having out of the blue and not every time but occasionally it acts like it needs the peddle pumped. Cranks but no go, I stop and press the gas and it starts up. But again doesn't do this every time. I changed the fuel filter a year ago. Any suggestions would be welcome....

twinboat · 12-12-2017, 05:46 PM

Following

mrt_1111 · 12-12-2017, 11:01 PM

i would change fuel filter and check fuel pressure. could be water or something in the gas, go through a tank of gas, fill it up and see if it still has the problem.

Sweetbriar · 12-13-2017, 04:56 AM

First thought that came to mind is the fuel pump is getting weak and fuel pressure might be low at starting. If you can check the pressure with the engine off and cold. Not 100% sure what the pressure should be but 40 PSI sticks in my mind for some reason. Just turn the key to run and check it. The pressure should come up quickly. Once the engine is started it should hold steady.

Waiter21 · 12-13-2017, 05:11 AM

Electronic fuel injection.

Sounds like the fuel pump or the pressure regulator. Normally, the fuel system is tight and will hold pressure for weeks after the engine is shut down, and only takes a second to build pressure back up when you start the engine.

If the fuel pump or regulator is leaking, it won't hold pressure when shut down, and will take longer to build up system pressure when you are attempting to start the engine.

homeless · 12-13-2017, 08:33 AM

How do you check fuel pressure? Is the fuel pump in the tank?

OLYLEN · 12-13-2017, 09:56 AM

Again, think I would change the fuel filter, not very costly and could be the problem. Next would turn key on and wait a bit of time to see if there could be a pressure drop that gets time to rebuild pressure.

LEN

twinboat · 12-13-2017, 10:14 AM

My understanding is that the fuel pump only runs a few seconds when key is just turned on. Then it runs when cranking or when the engine is running.

House Husband · 12-13-2017, 07:08 PM

Quote:

Originally Posted by homeless

How do you check fuel pressure? Is the fuel pump in the tank?

There is a port on the fuel rail that you can attach a fuel pressure gauge to.
Yes the pump is in the tank.

Richard

homeless · 12-14-2017, 09:46 AM

Assuming it is the pump leaking. Is there an additive I can add to improve the life of the seals?

House Husband · 12-14-2017, 05:04 PM

Quote:

Originally Posted by homeless

Assuming it is the pump leaking. Is there an additive I can add to improve the life of the seals?

The only cure for a bad fuel pump is replacement. There are no patches.
Until you check the fuel pressure before and during start up, you don't know if you have a fuel problem.

Richard

RELHUB · 12-14-2017, 05:13 PM

Quote:

Originally Posted by homeless

How do you check fuel pressure? Is the fuel pump in the tank?

On the fuel rail is a valve ( looks like a bike tire valve with a CAP on it ) you would attached a pressure reader. Then start the engine and look at the at the numbers on the gauge. You will need to find out what the minimum reading should be ( I thinks 50 + PSI is the min.) and also what the numbers need to be when different RPM's.

NOTE this fuel rail contains fuel under high pressure make sure you have safety glasses on so you do not get fuel sprayed in your eyes.

FYI .... YOU TUBE has video on how to locate and hook up a fuel pressure tester.

twinboat · 12-14-2017, 05:42 PM

The problem with testing the pressure is you need to watch the gauge when it cranks but doesn't start.

You didn't mention a running issue when it starts, so the pump may be working fine when it runs but doesn't run at all when it don't start.

I bring this up because I've read on this site that if the V10 don't start, as a test, you can bang on the bottom of the gas tank to maybe get the pump running.

daveandcarol · 12-14-2017, 09:56 PM

Bang on the... gas tank. HA!

Many years ago, I owned an old MG. The fuel pump would occasionally cut off while driving. I would reach behind the seat area and 'rap smartly' (as the British owner's manual put it) above the fuel pump area and it would start back up again. I know this doesn't help you any but thanks for bringing back the memory. For all its faults, I really enjoyed that old car...