Kasrel928

OK guys, I have a starting issue. I am in the process of recommissioning my 81 928 4.5L RoW 3 Speed Auto that has been off the road for 8 years due to a fuel issue from the previous owner.

THE PROBLEM:
Car will start for 0.5 to 2 Seconds and then dies (ONLY ONCE). Will not fire at all after dies, just continues to turn over while holding key. Last time revs went up to 2500rpm before engine cut (after reinstalled injectors)

WORK DONE TO SOLVE ISSUE:
- Previous issue with no fuel through fuel distributor. Bought kit and rebuilt. Installed and now a small leak is present from one side of distributor when turning over. I am considering using gaskget glue on the diaphragm, wonderin if its il advsied. Can't seem to stop the leak between the two mated halfs of the distributor. Is there some sort of calibration that must be done to ensure that fuel distributor is not providing excess fuel pressure? I have checked that fuel is flowing through the return line and have played with the needle at the rear of the fuel distributor, but am not keen to do so again as the last time it fell down into the bell housing which was not fun to fish out.
- Checked the cylinder compression, reading 130psi and 180psi on the first two (nearest to the front) on the right hand side (me facing the car). I really should learn the cylinder names (please don't hate :P) - I should note that this reading was only done once and was not for all cylinders and was done before the injectors were cleaned but after the distributor was rebuilt.
- Pulled all injectors. VERY DIRTY. Cleaned intensely and put back into car. Spray pattern improved but not perfect.
- Pulled distributor cap and sanded points underneath for good spark. Improved spark at plugs
- Checked all leads. Good spark to all plugs.
- Replaced spark plugs. Dirty and drenched in fuel from starting. Assumed too much fuel entering the intake manifolds via injector when trying to start and drenching spark plugs. Perhaps the reason for not being able to start again. Pulled them and cleaned them. Reinstalled and no start.
- Replace all visible vacuum lines showing signs of age. Only guess as to the correct setup. This is my first shark.
- Cracked all hard lines to ensure fuel flow to injects. Plenty of fuel.
- New fuel filter at rear. Good, clean fuel now.
- Removed dead in tank pump replaced with fuel sieve.
- Pulled intake manifold off and cleaned throttle body as well as the air flow plunger under the distributor (forgot the name of the thing, sorry guys )

EXISTING ISSUES (PERHAPS RELEVENT)
- Hissing from fuel pump at rear. Suspected pressure loss through hiss? But high pressure seems to be the issue here.
- Dripping leak from fuel tank at rear. Please PM me if you have a spare tank i could get from you (located Brisbane, Australia)

RECENT WORK DONE BY ME (PERHAPS RELEVENT):
- New timing belt.
- New PK tensioner.
- Cams in timing
- Cosmetics and some minor fuel tank fixes to trying and plug leak.
- Removal of air pump and all leads to the cam covers

POSSIBLE THOUGHTS TOWARD THE PROBLEM:
- Have not touched the warm up regulator or start up injector but have checked the WU Regulator for power which it is receiving. Is it worth to clean it out? I will also pull that start up injector to make sure it's nice and shiny and spraying as it should. I left the injectors in some fuel cleaner over night and scrubbed them in the morning and then pushed metho and cleaner through them as well as throttle cleaner with my trusty air compressor to improve the spray pattern. I would replace but they're about $100AUD each, which is a BIG chuck of the budget which I'd rather put toward other things.
Car has run previous to timing belt job, though was REALLY rough. Total running time is approximately 30 minutes in 8 years. I will link the youtube video of it running which may help.

Really scratching my head here. I can't seem to find the problem. I will get some photos up here for you to check the lines and see if I've missed anything. Please throw any and all ideas here, I'm really running out... :/

Thanks

MainePorsche

The fuel leak must be completely mitigated first.
Possibly be the pressure retention valve right off the pump. This would cause a drop in fuel line pressure in addition to the leak if it is from elsewhere.
Evaluate this valve and mitigate the leak before you look at any other part of the system. Once taken care of you can move on to other elements if you need to.
Best Wishes.
Be careful.

Kasrel928

Wouldn't the presence of wet spark plugs and a leak through the mated fuel distributor indicate high fuel pressure, not low? That asside, the leak is a real worry as it is a danger being so close to the 12V fuel pump...It is definitely a priority to fix, but can't seem source a replacement

MainePorsche

Read over the fuel soaked plugs. All leaks fixed first, then consider more esoteric things.
Fuel pump, and other things from 928 International or 928 Rus.
Below is a pic of the retention valve (8). If you replace things there don't forget new sealing rings.

Wisconsin Joe

Where are you? I thought fuel pumps were readily available (here in the US) through the "usual suspects."

That car is CIS (K-jet). It's really particular about the pressures at various places in the system. You can't get it right by "playing with" the fuel distributor. If it's been sitting for a while, then it may well need to be fully cleaned out. I'm not really familiar with CIS, my car has LH.

But there's a guy who knows the early cars pretty well. He's on here, and has a shop. And a pretty comprehensive website.

http://928classics.com/index.html

davek9

I think he is located Down Under Joe.
"...Please PM me if you have a spare tank i could get from you (located Brisbane, Australia).."

Rocinante

Did you ever get her running smoothly?

s54venture

It appears so, he edited the original post and the video in it shows a running 928.

Rocinante

So he creates a long post asking for help, and then solves the problem, creates and posts a video with a solution 17 minutes later? ...and still keeps posting in the thread?

Or is it too late in the day and I'm getting confused (again!)

Mrmerlin

who knows whats going on here,
\ I don't understand either

michaelathome

I think he ment to say things he has "tried" to solve the problem. If you listen to the video the car sounds horrible.

That being said I don't know CIS engines at all. Sorry I can not help.

Michael