50% is steep- we go more like 25, still a deal,regardless. " Induction service" is most likely cleaning the butterfly with a can of carb cleaner... something you can do yourself. It can help the idle. I don't know about Isuzu motors , but the ford 4.6 V8 has a regular need of cleaning. Ford finally issued a T.S.B/ about it some time back. Pull the intake snorkel, fiddle around with the metal flippy plate on the engine... if you see alot of carbon(the black crap) built up on the edges and back... squirt with carb cleaner till clean. reassemble... drink 40 bucks worth of beer... put 60 in bank or tank,your choice. wayne