911 2

My 3.3 Turbo has recently been difficult to start, harder when hot, let it cool down and it starts,
On cold start it just about starts and then misses or runs bad for about 10 seconds and then after that it is perfectly fine
I have been told it is the fuel accumulator, that it s faulty and to remove and pass air through the top, if the diaphragm is split then air will pass out the bottom but in some cases this may not happen but accumulator can still be faulty
Removed it from the car, that was a hard job as its tucked far in the left corner, tried the above test and no air comes out the bottom
When i released the fittings the two top lines had no fuel come out but the single lower port released a fair amount of fuel, not sure if this means anything
Is there any other way I can test if the accumulator is faulty.

Black_Hat

Hookup a CIS pressure gauge
after testing cold, then warm then boost enrichment
turn offf fuel pumps and see how long the system holds pressure - IF the system pressure drops too fast than you have a Bad Fuel accumulator
Porsche has a spec for each of these
I'm away from my books, so I cannot look it up for you

911 2

Thankyou, I have removed the accumulator is there any test I can do on the bench
if not i assume I should put the accumulator back in
Any links please where i need to connect the fuel pressure gauge and how to carry out the specific tests

Black_Hat

Black_Hat

Disconnect the power plug from the WUR to test Cold

I pull the fuel pump relay and jump power to fuel pumps with a wire

hook up the power plug to WUR to check warm

once warmed up to check boost fuel enrichment hook up a line to the boost pressure side and apply air pressure -NOTE _ be very carful with air pressure only apply 5PSI the add a little till you see a drop in pressure
or you "Can" blow the internals on the WUR

wicks

If it's the original (or very old) accumulator, you want to replace it anyway.

911 2

new one is on order