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engine miss

DougMc

New Member
I need an expert! 1990 5.0L mass air engine running stock ford injection components except it is running a Ron Francis stand alone harness and a Tanks Inc. fuel pump. To duplicate my issue, you would put a toggle switch in your ignition wire and somewhere between 50 and 70 MPH you cycle the switch fairly rapidly. Total rapid engine shutoff and restart that can be a little violent. It does not do it every time and almost seems to be affected by engine temperature although that could be just my imagination. I will say that every single injection and electrical component has been replaced except the wire harness and the fuel pump. I can't wrap my head around this being a fuel issue due to the fact that the pump runs and delivers a constant supply of fuel no matter what speed your traveling and is really not effected by engine RPM's.
I am completely out of ideas and really need some opinions!
 
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