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Electrical 92 Fox 5.0 no start

  • Thread starter Thread starter xwhiskeyechox
  • Start date Start date Apr 24, 2025
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    fox body 5.0
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xwhiskeyechox

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  • Apr 24, 2025
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So I have a 1992 5.0 with A9P ECU. Engine and T5 trans completely rebuilt. It start having issues starting and now isn’t starting at all. New Distributor, new capacitors in ECU, new injectors, fuel rail cleaned after finding clog, fuel pump works, I have spark at the coil and plugs. Still no start but does turn over and will fire at the throttle body. Anyone have suggestion OR a way to test the injector pulse at the ecu?
 
Last edited by a moderator: Apr 24, 2025

Noobz347

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  • Apr 24, 2025
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xwhiskeyechox said:
So I have a 1992 5.0 with A9P ECU. Engine and T5 trans completely rebuilt. It start having issues starting and now isn’t starting at all. New Distributor, new capacitors in ECU, new injectors, fuel rail cleaned after finding clog, fuel pump works, I have spark at the coil and plugs. Still no start but does turn over and will fire at the throttle body. Anyone have suggestion OR a way to test the injector pulse at the ecu?
Click to expand...

Have you check these guys out?

Home - ECU Exchange

ECU Exchange specializes in the re-manufacturing and repair of engine control modules.
www.theecuexchange.com
 
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xwhiskeyechox

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I’ll check them out but wanting to verify that it is the ecu that’s the problem
 

Noobz347

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xwhiskeyechox said:
I’ll check them out but wanting to verify that it is the ecu that’s the problem
Click to expand...

Pull codes.

https://www.amazon.com/INNOVA-3145-Ford-Digital-Reader/dp/B000EW0KHW?crid=15Z9SHRSKH8JL&dib=eyJ2IjoiMSJ9.l4qfZfxsv0vva_WTj7XfCVi5CJKO23VHfZS-uzH3jOuOsEJK9OIelfrYCLnQlgHWQTnctusZDkURvA-WzvNW9w_CLRXDECzQtwlJVsjcPAhYURy8LvjK3UEMw8OOCR_0VxiK-5nI34ZAEnhAdE5nq_CjyAo4wPo-MUUELv2qsBBS2XaOi5xnfVMFeR3vW4WPfS1wK-FaENpcLjPgOJGWkTOErCHJ_VFCuECucS2u-2BTfmNEPvUFn1bejetr0TRQLdAqxANwnftrnJx0AaktjKTZcsSBNKYRtW6h9dAJ05M.9GfYU1-Y0fSFTVU42Z22SJrHeuLUKyruns0sY9SnGRU&dib_tag=se&keywords=ford%2Bobd%2B1&qid=1745558757&sprefix=ford%2Bobd%2B1%2Caps%2C210&sr=8-1&th=1

You will either get trouble codes or an all-clear, separator code.
 
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AeroCoupe

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To echo what Noobz posted the CEL only illuminates for emissions related codes so there can be codes and the CEL will not illuminate so the first thing we should do is check for codes when trouble shooting engine related issues with these cars.

You can get noise lights at a parts store. These are attached to the injector wiring connectors and will flash when the pulse is sent to the injector.

If all lease fails then go here and we cannot stress this enough, follow the damn instructions to the letter, do not skip around (even if you already did what it’s suggesting previously), and read it all the way through before you start. This guide is from years of working on these cars and the guy that put it together has helped a lot of us get our cars running again.

Thread 'Cranks OK, but No Start Checklist for Fuel Injected Mustangs'

May 22, 2006
Cranks OK, but No Start Checklist for Fuel Injected 5.0 Mustangs model years 1986-1995

A word about this checklist before you start: it is arranged in a specific order to put the most likely failure items first. That will save you time, energy and money. Start at the top of the list and work your way down. Jumping around will possibly cause you to miss just what you need to see to find and fix the problem. Don’t skip any steps because the next step depends on the last step working correctly.


Revised 26-Jul-2017 to add fuse link diagram.

All text applies to...
  • jrichker
  • Replies: 93
  • Forum: Fox 5.0 Mustang Tech
 
Last edited: Apr 25, 2025
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