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fuel pressure accumulator problem, or is it?

Posted: Mon Jan 27, 2014 11:45 pm
by G5 VWS
I took my scala out for a drive for the first time in ages today

It was running great and I was really enjoying my drive. that is until I stopped for fuel after going to pay for the fuel and getting in back into the car , it was really difficult to start. it would turn over for ages then splutter a bit, cut out and all sorts of silliness I finally got it started and it ran absolutely fine the whole way home.

I let it cool down when I got home, then tried to start it, and it did so first turn of the key. I took it a quick drive to get it up to temperature to see if the issue reoccurred which it did, would not start when up to temp

I've done a bit of reading online about this issue and it appears that the fuel pressure accumulator could be the issue

Has anyone any experience of this issue or Is there anywhere else I should be looking to resolve this problem?

It's a 1.8 dx injection

Thanks in advance

Re: fuel pressure accumulator problem, or is it?

Posted: Tue Jan 28, 2014 11:32 am
by chopperoli
With a gauge, do the famous K-jet pressure leak down checks to identify loss of pressure.

In order, the likely candidates:

A leak (dribbly injectors, cold start injector, even the smallest weep from any fuel lines or joints)
Fuel pump non-return valve failed
Metering head pressure regulating valve (o-rings)
Accumulator failed

Re: fuel pressure accumulator problem, or is it?

Posted: Tue Jan 28, 2014 6:16 pm
by G5 VWS
I'm pretty sure its the accumulator that's at fault

its weeping from the screw on the back plus I discovered the lift pump in the tank is fubar too.

will probably need a new main pump too if the lift pump has starved it of fuel

Re: fuel pressure accumulator problem, or is it?

Posted: Tue Jan 28, 2014 6:38 pm
by mark1gls
Just replace the lift pump first and see how the main pump is, I went throught 5 lift pumps before my main pump gave up at about 220,000 miles!
The main pump is a right pain to change as all the connections get nice and rusty under there.

Re: fuel pressure accumulator problem, or is it?

Posted: Tue Jan 28, 2014 7:18 pm
by Tim_R
It certainly doesn't sound healthy if its weeping petrol at the back but there's a couple of other parts to consider as well.

There's 3 components to keep the fuel pressure in the line to the metering head after switch off. At the metering head there is the fuel pressure regulator, just in front of the pump is the accumulator and on the main pump itself is a one way check valve. The check valve and FPR effectively seal the line from the pump to metering head at each end and the accumulator is a sprung loaded diaphragm, to keep the petrol from vaporising in the engine bay end of the line after shutting off the engine.

When I didn't have a check valve in my system, I had to prime the fuel pumps 2 or 3 times before I could get the car to start as there was no residual pressure being held

A dead lift pump normally means the car won't pull as well and hesitate and stumble due to fuel starvation and poor pressure from the main pump.

Re: fuel pressure accumulator problem, or is it?

Posted: Tue Jan 28, 2014 7:48 pm
by chopperoli
Yes I already mentioned those 3.

If the accumulator leaks from the back then the diaphragm is split and it needs replacing

Re: fuel pressure accumulator problem, or is it?

Posted: Tue Jan 28, 2014 8:29 pm
by ianaudia4
Give this company a call ref accumulators, never dealt with them personally but was recommended by a colleague.

KMI Petrol Injection
Unit 5D, Diamond industrial Centre, Works Road, Letchworth Garden City,
Hertfordshire, SG6 1LW, England.
Phone +44 (0) 1462 682432