79 930 reality check part 2

[ayebaal]

Part 1 was checking that the fuel distributor was passing fuel to the hard lines. It wasn't but was assured that the dist. was ok.

Pt. 2 pertains to fuel getting to the distributor.
Fuel delivery test as per Shop Manual: Taped into the return line but rather than tapping into the return line, I took off the banjo fitting at the rear of the fuel head (much easier to get at). Rather than getting 1170 ml. in 30 seconds as per the book, I got maybe 4 tablespoons but a lot of gas came out of the open line.
So, then I tried a delivery test by removing the line that comes out of the fuel filter and extending a hose to my graduated cylinder. Got over 1100 in less than 10 seconds.
Seems fast so I put a pressure gauge on it and it blew up the gauge (100 PSI). Low fuel pressure isn't the problem.

Any ideas??

[full quack]

I think the fuel path is tank-pump#1-pump #2-filter-accumulator-fuel head-injectors.

So if you have pressure at filter, but none at fuel head...could be a blocked accumulator, if that ever happens???

How are you keeping the pumps running during your test procedures? Are you depressing the air sensor plate to get flow through the fuel head to the injectors??

Mark

[boosted79]

If you dead headed the line from the filter with the gauge, yes you will get very high pressure. do you have a CIS test rig?