Dave Johnson
New Member
Hi I just finished installing a brand new coyote crate motor in my 2015 mustang after I bent valves in the original one. Brand new motor from Ford Performance through Summit racing and I'm getting an intermittent lean condition and random misfires, usually mid throttle, cruising with the revs up aroung 2-3k. I upshift into overdrive and it clears itself up after maybe 10 seconds but it seems to keep coming back. This is a brand new motor complete with injectors, intake, throttle body, almost everything. I still have the factory fuel pump, o2 sensors and computer. I did upgrade to the BBK headers and cat delete, and have the proper tune for those. Same difference on factory tune or new tune. Any of you guys have any ideas what could be doing this?
Update: new O2 sensors upstream and no change. Still stuttering just a little while cruising and then the way lean condition and bad bogging for about a mile of driving.
Update: new O2 sensors upstream and no change. Still stuttering just a little while cruising and then the way lean condition and bad bogging for about a mile of driving.
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