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Discussion Starter #1
Hello everyone!

I've got a 2016 with a touch over 100k on the odometer and its running great. I recently noticed a ticking sound, much like what you would hear when a car is misfiring and not all cylinders are working properly, but very muted. The engine pulls strong and smooth, so its not a cylinder not firing

  • I can only hear it when i'm next to curbing or a median and accelerating, so the sound gets reflected back towards me.
  • I found if i put the van in manual mode and force it into 4th gear, I can almost always recreate the ticking sound at right about 2k RPM. I initially noticed it when accelerating hard enough to load the engine, but not hard enough so the van downshifts into a lower gear, thus trying it in manual mode.
  • In neutral, if i bring the RPMS up to the same 2k range, no sound. Engine sounds smooth.
  • It seems to occur more often when the engine is cold, but I can still get the ticking sound to happen from time to time.
Any thoughts or advice?
 

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Sorry if this is way off your situation, but two times I've had ticking that I thought was mechanical. The first time it turned out to be a stone in the hub cap. The second time it ended up being the small float in my propane tank knocking back and forth (camper conversion).
 

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Discussion Starter #5
At first I thought it was a plastic bag stuck to the underside, flapping in the wind. Maybe I'll do a thorough inspection just to make sure there aren't anything creating odd sounds and report back. :)
 

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Diagnostically (is that a word?), does the ticking vary with engine speed?
 

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Discussion Starter #8
So it turned out to be a broken tab on the engine cover under the van. Simple and easy fix!

To answer your question, the ticking / flapping sound interval would increase with speed, but it was associated with wind speed, not engine speed.

Thanks for all the input.
 

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Discussion Starter #9
The ticking sound is back and I've narrowed it down to putting the van under load between 2k - 3k RPM. Happens easiest going uphill from a stop, getting to about 30 MPH and then accelerating moderately.

I had some unleaded 100 octane race fuel leftover I threw in the tank to see if that would make a difference, and unfortunately no.

I have it at a local indie shop right now for them to run diagnostics on it as I'm worried it's some form of detonation. Will report my findings.
 

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Discussion Starter #10
Oddly nothing seems to be wrong in terms of diagnostics. No detonation, no codes thrown. Shop says the noise seems to be coming from the turbo, but it looks to be in good condition. So very odd.

Anyone else experience this?
 

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Discussion Starter #12
Thanks for that, but unfortunately it's none of that. Only happening in a small window of operation as described above between 2k - 3k RPM and under load. In neutral, the engine is smooth as butter when revved, gets great MPG, and the engine is not consuming any detectable amounts of oil.

I thought it was the underside cover flapping in the wind, but that's definitely not it.
 

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I know a van with similar symptoms but had over 170k miles on it. The noise went away after using Lucas fuel additive/ cleaner on two consecutive fills up. The guy ended up replacing injectors and the noise was gone.
 

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Discussion Starter #14
Thanks for the insight. I will try the fuel additive and look into injectors. My Metris as about 102k miles
 

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Discussion Starter #16
I am almost 100% certain this isn't the interior as I can only hear it with the windows down and when I'm driving next to a median.

When I bought my Metris, the interior rattle and road noise drove me bonkers, so I pulled off all of the panels, added sound deadening material, and even padded the base of every push pin on the panels to reduce/eliminate as much as possible.
 
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