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99 mustang misfiring during hard throttle

2K views 5 replies 4 participants last post by  tfalk 
#1 ·
Question: my 99 4.6 is misfiring under hard acceleration could this be plugs, coils, coil packs? I have a broken o2 sensor wire.
 
#6 ·
Just found out i have a small leak from manifold gasket, could that cause it also?
Absolutely, any time you have unmetered air entering into the combustion chamber,
the engine could lean out and misfire. Not a good thing with hypercraptic pistons...
 
#4 ·
When mine was misfiring, I had it ran at Oreillys and it was cylinder 2. All I had to do is change tat spark plug and it cleared it up.
 
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