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1981 928 5 Speed Start but no run

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Old 08-02-2016, 09:15 PM
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PorscheBubba
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I will verify green wire does not contact block and I thin L Jet also because it was used in US cars for 81 K Jet was used in all others from what I read. Also it has wires to injectors and K Jet from my understanding has no electrical connections to injectors.
Old 08-02-2016, 09:47 PM
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jetson8859
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Your best suppliers for 928 parts are, in no particular order listed below. These folks know all the small differences between model years and 928s are their primary, if not only, business. They can also guide you through any repair from a parts perspective to include items you didn't know you needed to complete a repair. You can find phone numbers on their websites. Strongly suggest you call as most websites don't list everything they carry and besides they all love to talk 928s!

928srus.com - Roger or Laura
928intl.com - Mark or Tom
928motorsports.com - Carl
928gt.com - Dave or Jeannie

Good luck with the car!
Old 08-02-2016, 09:58 PM
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Originally Posted by jetson8859
Your best suppliers for 928 parts are, in no particular order listed below. These folks know all the small differences between model years and 928s are their primary, if not only, business. They can also guide you through any repair from a parts perspective to include items you didn't know you needed to complete a repair. You can find phone numbers on their websites. Strongly suggest you call as most websites don't list everything they carry and besides they all love to talk 928s!

928srus.com - Roger or Laura
928intl.com - Mark or Tom
928motorsports.com - Carl
928gt.com - Dave or Jeannie

Good luck with the car!
I appericate the information because people who specalize in something know what they are doing. I am in SC and was in GA at big waterfall not long ago then seen a braves game. Thanks
Old 08-03-2016, 05:58 PM
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Replaced both relays now fuel pump does NOT RUN ALL THE TIME. Car will run using carb cleaner so know its fuel problem. I will be working on it all day so and advice please share. Thanks
Old 08-03-2016, 07:56 PM
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mnotz
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Do you have a NOID light to check for fuel injector pulse while cranking? Or sometimes you can hear the injectors click with a stethoscope or even just a screwdriver held onto the injector and your ear...
Old 08-03-2016, 09:09 PM
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PorscheBubba
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1. NOID Light and NO pulse or light of any sort.....its set from Autozone the Bosch FPI light
2. Has 12v on both pins of injector wire that plugs into injector
3. I dont follow electrical diagrams very well so if someone knows path of the 12v please let me know.

Car still does same, it runs 2 seconds unless using carb cleaner then it runs good.
Old 08-03-2016, 10:11 PM
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Mrmerlin
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did you take the connectors off the fuel injectors?
If so its possible you have shorted one of them
Old 08-03-2016, 10:14 PM
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PorscheBubba
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Originally Posted by Mrmerlin
did you take the connectors off the fuel injectors?
If so its possible you have shorted one of them
1. I removed 1 plug from each side
2. I sure hope its nothing stupid like an alarm system
Old 08-04-2016, 12:39 AM
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I found this not hooked up and its for fan because it makes fan run. With switch on 1 side is 12v.........2nd wire is ground. Anyone have pics of what this is suspose to connect too?
Old 08-04-2016, 12:40 PM
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Can anyone offer me any leads to someone that I can PAY for phone/email support to diagnose this issue? I have never used justanswer because not being able to call them is crazy to me. You can PM me the contact or they can PM me. Thanks
Old 08-04-2016, 01:01 PM
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GlenL
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Posting here is about the best. If help has dried up it's because the hive mind isn't seeing clear answers.

That connector does look like a fan connector. Sounds like someone disconnected it because the fan was always running. It should run with the AC on or when the thermoswitch in the left-lower-front corner of the radiator closes. It should only be on when the car is on and not run after shutdown like some cars do.

So...

You've confirmed that the ignition is working.
The Fuel pump is working correctly: runs for a moment when car turned ON and runs when engine turning.
Car stalls out after a couple of seconds and no fuel is suggested by that.

Just to confirm, it will start on its own, at least sometimes, without carb cleaner or other canned spray fuel?
Old 08-04-2016, 01:07 PM
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Yes it will always start on its own and run for about 2 seconds which I suspect its running off the cold start injector.
Old 08-04-2016, 01:37 PM
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GlenL
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Originally Posted by PorscheBubba
Yes it will always start on its own and run for about 2 seconds which I suspect its running off the cold start injector.
This makes sense. This leaves that the injectors aren't firing. Points to electrical problem. You've checked this previously. I guess it's time to go back through that the ECU is powered-up, getting signals and making signals.
Old 08-04-2016, 02:03 PM
  #29  
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Yes but I dont understand the flow by looking at diagrams. I need someone to tell me wire such and such is responsible for injector pulse.
Old 08-04-2016, 02:12 PM
  #30  
neilh
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Carefully check the plug at the Transistor Ignition unit. The 'green' wire goes there, and from there a regular green wire goes to the fuel pump relay, the ignition control unit, and the Tach.
Does the tach kick when you get it to run?
The car will start and run momentarily if the TIU is bad, then die.

Send me a PM and I'll send you my phone number, I'm in Raleigh.


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