if you rip the fuel evaporation emission box out from under a crown vic is it alright to drive
Not a great idea to do it intentionally. The "Check Engine" light will come on and the computer will go into a failure mode. I do not know what kind of effect it will have on performance but knowing the EPA - I'm sure that it will slow down something. If it was an accident and you intend to replace it ASAP, you'll be ok but you will need to clear the codes later. I've replaced several that were packed full of dirt.
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