1996 Ford F 150 Eddie Bauer. Engine Size : 4.9.

Question: My truck is missing even after I changed the spark plugs and wires. What will cause it? Some people say it is the intake gasket. I am not sure so I have not changed that yet.

Answer: Engine misfire can be caused by many things. If the plugs and wires did not help, it could the ignition coil or an engine mechanical problem. It all depends on when it happens. An intake manifold leaking vacuum will usually just give a misfire at idle. This will cause a lean condition and rough idle. If it is missing under acceleration, then that is usually ignition related. If happens at all seeds, even steady, that could be a valve problem. As you can see there are many different causes depending on the exact nature of the engine misfire. A scan of any engine codes, even if the check engine light is not on, may give an indication as to where the problem is.

F-150 Engine Tapping Sound

Question: I have an 04 f-150 5.4 l. I am getting a tapping sound at idle. My mechanic says it is something I have to live with. I have approx. 239,000 miles. Any thoughts? Thanks.

Answer: Well, he is probably right. A tick at idle could be a worn rocker arm, pushrod, lifter, cam shaft, etc. With that many miles it would not make sense to take the engine apart and look for the noise since many parts will show wear on them. You would be putting a lot of money into your Ford truck just to try to fix a tick that may or may not ever get worse.