I was worried about the same issue but the way i see it, the Subaru instructs to spray half the can (75g) into the engine and since its for subbie's displacements are at least 2.0l right? I have a 1.6l so i sprayed just over a quarter when engine is off and sprayed the rest while running.
Get the Subaru UEC Beeza, you won't regret it... i've tried a few other brands of engine cleaner and throttle body cleaner before and this by far is the best. I was skeptical also since no had previeously written a review here, but after scouring the net, nothing but the greatest of praise for this product.
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