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BionicBalls · Joined: 05 Jan 2009 Posts: 642 Location: Charlotte, NC

I have been trying to get all the gremlins out of my CIS system forever. I have a rebuilt fuel dizzy.

New:
WUR
Injectors
Accumulator
Thermo Time Switch

I was previously running a fuel pump from a 951, but I was experiencing warm start problems. So I put in this fuel pump:

http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&item=390149130189&viewitem=&sspagename=STRK%3AMEWNX%3AIT

which has higher pressure. Now I can't get the car to start. WTF?!?! I thought that maybe the higher pressure in would mess up the fuel mixture at the dizzy. So I took injector line 1 off at the dizzy and turned it clockwise until I got fuel just barely trickling out. No start. So I pulled the injector. The injector is not opening. If I remove the injector, I have fuel dripping out so I've got fuel to it. Is the injector just stuck closed or am I simply not getting enough pressure to make it open? Any feedback is appreciated.
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1980 924 NA
1982 931

Ozzie · Posted: Wed Mar 31, 2010 10:05 am Post subject:

do a fuel pressure and fuel flow test as per the haynes manual.
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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

BionicBalls · Joined: 05 Jan 2009 Posts: 642 Location: Charlotte, NC

Yea, I need to go ahead and order one up. Also looking for a CO tester for the fine tuning. Any brand suggestions?
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1980 924 NA
1982 931

dpw928 · Joined: 02 Nov 2002 Posts: 1860 Location: owasso, ok 74055

Check our wiring to insure the connections aren't reversed. IIRC the positive connection goes on to the smaller post and the ground to the larger. If that is correct, perform a output volume test.

Dennis
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81 931 5 sp
78 928 5 sp Silver
78 928 AT Euro Black

BionicBalls · Joined: 05 Jan 2009 Posts: 642 Location: Charlotte, NC

You're correct. The pump is marked, and the positive uses a 7mm nut to secure it and the negative uses a 8mm.

With the 951 pump, I was getting anywhere from 0-2 bars of pressure upon start. With this pump, I'm getting 3-4 bars. I will check the volume output though. Is this pump meant to be used in conjunction with another pump?
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1980 924 NA
1982 931

dpw928 · Joined: 02 Nov 2002 Posts: 1860 Location: owasso, ok 74055

The pump listed was a 6 bar pump. It should deliver about 1100+ ML in 30 seconds. Have you checked the in tank strainer to see if it is plugged? Fuel filter plugged?

Dennis
_________________
81 931 5 sp
78 928 5 sp Silver
78 928 AT Euro Black