Slight ticking noise ford 4.6. Normal? (With audio clip)

Hey everyone, my 2005 mustang with the 4.6 engine is making a very faint ticking noise at idle. It does NOT get worse with revs. Sound clip attached. Not sure if this is normal (fuel injectors) or something like a valve lifter going bad? thoughts? thanks.

if you are talking about that one click sound in the clip, that sounds like the a/c compressor either coming on or going off.

I hear what you’re talking about but was referring to just the sound clip in general

well then that sounds like a exhaust leak, but its hard to tell from here

Does the ticking get faster w/increasing revs? In other words does the ticking rate increase w/increasing rpm?

Common causes of engine ticking sounds when the ticking rate changes w/engine rpm:

  • Oil level or pressure is low, check dipstick.
  • Valve clearance or hydraulic lifter problem.
  • Water pump about to go belly up.
  • Frayed accessory belt
  • Accessory bearing on the fritz
  • Engine pinging

Fuel injectors tend to fairly quiet b/c they are stuck inside the engine, but if heard, make more of a whining or buzzing sound.

Suggest to do some experiments to decide for sure what the ticking rate is associated with. For example, is it engine rpm? Wheel rpm (i.e. vehicle speed)? etc.

Get a length of hose and use it like a stethoscope to see if you can localize the source. I’ve heard fuel injectors tick, also a small exhaust leak.

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I can’t speak to the question of fuel injector noise on Ford engines, but I can tell you that the engines of some recent BMW models sound like a $10 K-Mart corn popper at idle speed. I had wondered whether what I heard was “normal”, but then Consumer Reports commented that these newer BMWs had very noisy fuel injectors.

The direct injection injectors are loud. Louder than the port injection injectors that most of us have gotten used to. I’m not sure you could hear injectors on an audio clip on a port injection rig like this 05 mustang.

As for the noise in the Mustang, may be a little valve train noise due to wear. It’s not uncommon for a 3 valve Ford V8 to make a few tick and clack sounds after several thousand miles. Actually, it’s more common than not.

I agree with the stethoscope to isolate the sound idea. I’d bet the sound can be pinpointed to coming from underneath one of the valve covers. Then you could remove the valve cover and take a look, if you wanted. I don’t think the noise is severe enough to warrant a ton of concern.


Those BMW direct injection engines do have loud injectors. Another possible source is spark arcing from one of the spark plug wires, if it has them. That can sometimes be seen in a completely dark garage with the engine running.