Mazda Protege weird problem

1993 MAZDA PROTEGE
152,000 MILES • 4 CYL • FWD • AUTOMATIC
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JUSTINMRICHEY
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  • 5 POSTS
93 mazda protege four cylinder starts fine alot of times then all of a sudden it wont start unless you unplug a fuel injector. it doesnt matter what injector it is you just have to unplug one and it will crank right up. we've checked all injectors and they are good, spark is good and timing is not off. we also replaced the pcm and it still has the same problem. Any suggestions
May 20, 2011 at 1:11 AM
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KHLOW2008
  • CAR REPAIR CONTRIBUTOR
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Did you try to retrieve for trouble codes?

Is the Check Engine Light indicating?
May 20, 2011 at 11:17 AM
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JUSTINMRICHEY
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  • 5 POSTS
Yep no check engine light
May 20, 2011 at 11:34 AM
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KHLOW2008
  • CAR REPAIR CONTRIBUTOR
  • 41,814 POSTS
Check the voltage at the fuel injectors. If they are below battery voltage, unplugging one of the injectors would increase the voltage to work the other injectors. You could have a loose wiring connection somewhere between the power supply and fuel injectors.

The other possible cause would be a bad ground circuit connection for the PCM or it is intermittently failing to ground the circuit.
May 20, 2011 at 11:47 AM
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