My neighbor squirted carb cleaner down the air port of his fuel injected 4 cyl. Toyota truck. (thinking it was a carb under the air filter) When it backfired he then hosed the engine down. Two days later it still won't start, so wet electronics can probably be ruled out. Question is, what bad things can happen by squirting carb cleaner down that air port? It ran pretty good before, he claims. Thanks, BA