A8 Engine Performance Test Questions with 100% Correct Answers

During a leak down test, air could be heard coming from the tail pipe. An exhaust valve not sealing When a cylinder head with an overhead camshaft is discovered to be wrapped, what is the repair option? check for cracks, straight in the head, and then surface the head Rack and pining inspection while in normal running position, movement is felt between the tie rod stud and the socket while the tire is moved in and out Torsion bars, exception are not interchangeable blue grey smoke is least likely caused by worn piston rings main bearing noise dull or deep sounding metallic knocking most obvious right after the engine starts up. connecting rod noise a light metallic tapping most noticable when engine is under a light load. becomes louder and occurs more frequently when engine speed is increased. will quiet down if you eliminate timing or fuel injection crankshaft end-play noise deep knocking sound that is usually most obvious at idle but diminishes under a load piston noise dull or muffled metallic rattle at idle or during light engine loads. will increase if you eliminate ignition or fuel injection. valvetrain noise excessive valve train clearance, worn rocker arms, shafts, lifters, camshaft or lack of lubrication hydraulic lifters consistent ticking sound. excessive clearance in valve stem & rocket arms. mimic the noise of worn valvetrain parts spark knock metallic pinging or ringing noise mostly under a heavy load or low rpm. preignition spark knock is caused by excessive combustion deposit or engine too hot loose drive belt high pitched squealing noise when engine is accelerated