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Would the O2 sensor keep car from cranking,an when running run rich?

(1990 Ford F-150)
in Kannapolis, NC on December 18, 2017
I have a 1990 Ford f150 4.9L. It doesn't wanna start,then when it does it burns rich. Replaced plugs, wires, distributor cap an rotor button as well as map sensor. Nothing has worked. Same problems. Blows black smoke an has a miss. Can someone give me a solution please.
What seems to make the problem better or worse? Not better
How long have you had this problem? Just bought it
Tags: won t start, running rich, ford, f 150
Displaying 1 answer & 1 comment
Popular Answer
on December 18, 2017
Possibly failed//ruptured *fuel pressure regulator* diagram .. Idle engine a couple minutes .. Turn engine off .. Remove the fuel pressure regulator vacuum hose and inspect for ANY signs of fuel in the hose .. Tap hose on palm of hand .. IF **any fuel** is present > replace the pressure regulator!
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on December 18, 2017
Also - possible stuck 'open' fuel injector .. *Hands-on* help from qualified personnel may be required.
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