I recently purchased an 03 Mach 1 and have noticed a mettalic tap around 2,000 rpm between acceleration and deceleration (unloaded). It sounds just like piston slap on an earlier mustang I owned. I have read through several forums and most conclude some valve train issues. That should not change due to engine load. It is more noticable when cold but remains when warm. Has anyone experienced similar noises due to spark knock or transmission noise that could be related to this. It really doesn't sound like valve or cam follower problems due to the frequency and engine load characteristics.

One suggestion as to turn up the radio and not worry about it. It just passed 100K miles.

 

Could it be the head tick that there was a TSB issued on from Ford on the 2003 4v cars? Ford had an issue with some of the passenger heads having valve guide problems. There was a TSB not sure how long they will honor TSBs though.

If its not that it could be a piston ring failure.

Those are my suggestions if it really is making a worse sound then a normal 4v.

 

Chris, Thanks for the reply. This may be normal for the 4V. I am going to cut open the oil filter on the next change to see if anything shows up. Otherwise I am going to just drive and enjoy.