I have a 2007 ford ranger with the 4.0 l v6 engine with about 250,000 km on it and about a week ago it started to tick when the engine went above 2000 rpm anything under 2000 rpm it would not tick

Im thinking it has something to do with the exhaust system but wanted to get some other suggestions on what it might be

Other than the ticking the motor runs smooth no knocking or anything like that that why i think its something with the exhaust

Hopefully its not anything major

 

Possibly an IgnitionWire shorting to frame?
How old are Plugs+Wires; should be renewed along with OxSensors every 100kMiles\12Years?

 

The plugs are the original ones the guy i bought it off didn't say he changed them