OOP's Let the smoke out of the engine

[stepding8]

Hi everyone, thanks for the help in advance.

96' Ford Explorer xlt 5.0 L

I let off on the ignition too soon, sorta back fired (light one), after which a plum of smoke came out from under hood. Tried starting again, started right up.
Loud suction now present rough surging at idle, around 45 mph rough down shift. Cruse control not as smooth now ( operating).
Started cold engine this morning, spray starting fluid around looking for vacuum leak. Engine smoothed out while spraying near the two fuel injectors on driver's side. Thinking I blew a o ring or injector out. (smoke from backfire)
Don't think a blown vacuum line would let smoke out.

Do you guys think I'm on the right track? your thoughts.

Not ruling out cracked manifold or blown intake gasket. thinking unlikely but possible. Know more when i get into it.

Looking at $37 dollars for intake gasket $97-$57 for injector.

Thanks again,

Steve

 

[stepding8]

Problem found

Thanks for looking.

driver's side of engine just above exhaust manifold two silver metal lines running side by side, I think there fuel lines. There's another metal line just out of eye sight behind those lines, with a rubber cap on it.

Engine back fired blowing the cap off opening the vacuum line causing the problem.

Slid the cap back on and started truck, back to normal again.

Simple fix,

Thanks again, good luck, be safe..