Hi there, have they valve clearance checked as one may have excessive clearance, caution must be taken if any adjustment is to be made as special tooling is required to replace adjustment shims, also check foe an exhaust leak around the manifold, start here.
May, 25, 2010 AT 6:06 AM
Is this an expensive undertaking? Would this also cause the car to sputter at low speeds?
May, 25, 2010 AT 6:41 AM
Hi there, with what you have added I would be looking at a short in a plug lead or a faulty coil, as excessive valve clearance normally won't cause the miss fire.
May, 25, 2010 AT 7:38 AM
The knock comes from the lower part of the engine. Would that have any impact as well?
May, 25, 2010 AT 5:42 PM
A knock from the lower part of the engine would indicate a possible bearing or oil pressure problem problem, I would be getting the oil pressure tested cold idle, hot idle and hot 1500RPM, post the findings here.