Hi robinv. Welcome to the forum. Something has been lost in communication here. You do not "replace cylinders", you replace an engine. Replacing the engine seems kind of extreme for a misfire condition. The place to start is with a diagnosis of the cause. A cylinder can misfire due to something as simple as a worn spark plug or defective spark plug wire. Those are the few parts left that are replaced as part of a regular tune-up. Burned valves that don't seal properly will cause a misfire that is felt more at idle that on the highway. A problem with the camshaft can cause one or two valves to not open properly but again, replacing the entire engine is REAL extreme compared to replacing the camshaft. That would be comparable to replacing the winshield because one bug got splattered on it.
To give a better-informed opinion, can you list the exact diagnosis the mechanic gave you? If not, a second opinion is definitely in order from another shop. You should not have been ignoring this misfire for months because little problems turn into big ones real fast.
Wednesday, June 30th, 2010 AT 1:48 PM