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'13 Boss 302 - Worried about noise

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So, I've had this 2013 Boss 302 for about 3 months and 1000 miles now and it seems to have developed a couple of noises that I'm concerned about.

There's a pretty constant ticking-ish noise, and down below there's what almost sounds like a very light and low pitched knocking noise.

Is this the stretch belt TSB noise? I'm going to try and pull the stretchy belt tomorrow when I get some more light to fool around with. I'm also going to try and make sure that's there's no part of the exhaust making contact with the body, I've seem some videos/info that indicate that that can be source of noise perhaps like this?

Any advice would be appreciated.


Because racecar.
Arizona, USA
Sounds like an exhaust leak to me.

Also regarding stretchy-belt; if you have a 2013 you shouldn't have that issue--you should have a separate front end drive belt with independent tensioner on the passenger side of the front end engine cover. (applied in production for 2013).
It must be an early '13, because there's definitely not a tensioner for the A/C belt. Anyway, I removed it this morning, no dice: tick still present.

Interestingly, at cold idle, it's not audible. There's a very faint sewing machine type sound, but no loud tick. With the red key, I don't really hear it until it goes to Trackey Idle, then it's very obvious.

Doesn't seem to audible above 1k or so RPM either, very loud at hot idle and off throttle deceleration.

I'm not experienced enough to say, but do you feel that points towards exhaust leak?


Because racecar.
Arizona, USA
Yeah very likely an exhaust leak. Would be easiest to pinpoint on a lift with the car running or (safely) on jackstands. Likely points: Connection from cats to midpipes, sidepipe connections, header gasket (rare).
Hello tk-421,

I also have a 2013 Boss with the same type of noise, a low light knocking type noise. I can only hear it....

· At idle only after the engine has been idling for at least 4 minutes, then the noise kicks in.

· It doesn’t make the noise all the time but seems to be more prevalent when it’s warm out (Spring/Summer).

· If you rev the engine the noise goes away.

· Doesn’t make the noise when you’re driving or revving, only when it idles

· With the track key and lopey idle it is still there but very faint, unless you are listening for it, you won’t be able to hear it.

I borrowed a friend’s mechanic stethoscope and listened to the engine while it was running and making the noise, I touched it to the block, heads, transmission and all in between and I could not hear the noise even though it was audible without the stethoscope. I also had an oil analysis done twice and both times it was exceptionally clean, no signs of unusual metal wear whatsoever. My car is still under warranty (extended warranty) until October 2019, I brought in in twice to have them listen to it and both times it wouldn’t make the noise (figures right?), however they did say that it may be something to do with the Variable Cam Timing (VCT) mechanism, that can be very noisy. Just wondering if you have had any luck diagnosing this noise since your post in December.

I tried to attach a sound file but it wouldn't let me. So how did you make out, were you able to diagnose it? Did you bring it to Ford for service?
Sorry for the late, late, late update, but I figured out the source of my problem.

Short story: The top nut on the passenger side header to cat flange had apparently vibrated off. The bolt hadn't fallen out so it was just rattling around.

I also pressured up the exhaust with the shop-vac and sprayed all the connections with soapy water. Found a number of small leaks.

Car sounds much better now though. Still a bit of sewing machine type noise from the motor but I think that's pretty normal from the Coyote.
people like this should get the Nobel award....that's brilliant.

Ha! Unfortunately, I can't take credit for the idea. I came across the technique somewhere online. Works pretty darn well, I just wrapped a rag around the nozzle of the shop-vac and stuffed it in one of the rear tips. Stuffed rags in all of the other tips.

I could actually hear the big leak over the sound of the shop vac, it was very obvious.

On a side note, that passenger side cat to header connection is very difficult to work on. Some curses were uttered trying to get a new bolt and nut on. Definitely need go buy a universal for my ratchet.
The AC tensioner mentioned above is well worth the add if you don't have it. I was having ticking for 500-1000 miles after oil changes and added that and it went away. It's even stated on the ad for the part that it cures the tick noise. I have a 2012 Boss.
Exp. Type
Exp. Level
10-20 Years
Detroit and dallas
No expert here but sounded a little like an exhaust leak. Possible?
Big-time my boss did that car down pipe round gaskets there is a knock sound there though, but audio tapes will trick you all you got to do is put your ear down there by the exit of the headers and you'll hear a tick especially when you first start it cold go right to it and listen

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