What will make my ford mastang gt have a ticking sound in the mortar
Valve train, timing chain, pistons/rod/main bearings... generally if the ticking is half the speed of the engine RPM the ticking is in the valve train (and most likely lifters). There are guides on the Web in identifying the various ticking sounds, a stethoscope will pinpoint where the noise is coming from, even a large screwdriver put against the valve covers, heads, or block and your ear will do (just be careful around moving parts), if you're not inclined to DIY a good mechanic would be your best bet.
You don't say how many miles are on it or if it is a V-8 or six, but if you are over 85-90,000 miles it might be piston slap. Do you know how the engine has been maintained? frequent oil/filter changes, etc.
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