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Ozzie · Posted: Sat Jun 25, 2011 10:30 pm Post subject: Fuel Problems

Car is running like crap.
Wont idle, stalls, no acceleration, hard starting.
Spent a day messing with injectors, CIS, checking fuel flow, spark and plugs.
Plugs are fouled, fuel in oil, fuel pressures all over the place.

Swapped the CIS and injectors are now working the same. Hardly at all.
Changed the plugs and oil.
Fuel flow is 600ml for 30 sec.
Intank pump is not running.

Disconnected the fuel hose between the two pumps and fuel only trickled out.
Took about 1/2 hour to drain the tank.
Then removed the in-tank pump

My immediate suspicion was the mesh being gunked up
However it was reasonably clean. Just a few large particles trapped.

I tested the intank pump with a meter and connected it to 12v, nothing.
I can only assume it has melted down inside and blocked the fuel flow as well.

Replacement on order.
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Porsche 924 1984 (UK import) NA
Its AUTO and its BLACK
Montego Black on black/red
Engineer of Electro/Mechanical Systems Maintenance

morghen · Joined: 21 Jan 2005 Posts: 9102 Location: Romania

i imagined it would be full of gunk too...mine was perfectly clean when i took it out.
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Supercharger and EFI kits
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Ozzie · Posted: Sun Jun 26, 2011 8:36 am Post subject:

When I checked it one injector was pouring out fuel, two were behaving normally and one didnt work at all.
Removed and blew out the injectors for no result.

Replaced the CIS which then gave me all injectors barely working with the flap lifted.

Checked fuel flow which was very poor and slow to build up pressure.

Changed main pump with no result.
Checked intank pump and it was open circuit on ohms and no current draw on amps. 12v was present.

Sounds like I found more than one problem.

When the pump arrives in a week or two I will have to set the AF mixture and timing again.
_________________
Porsche 924 1984 (UK import) NA
Its AUTO and its BLACK
Montego Black on black/red
Engineer of Electro/Mechanical Systems Maintenance

Ozzie · Posted: Sat Jul 02, 2011 7:39 am Post subject:

Back on the road again.

I think the cause was the power at the pump was 8V.
I checked the aux fuse box and replaced it with an aftermarket 8 blade fuse box.
Now have 11V at key on before cranking.
_________________
Porsche 924 1984 (UK import) NA
Its AUTO and its BLACK
Montego Black on black/red
Engineer of Electro/Mechanical Systems Maintenance