There are two strange sounds coming from my 2003 Ford V6 Mustang.

One is a medium clicking sound that goes away every now and then and is not as loud as before my last oil change (with marvel mystery oil added to it). I figure its the hydraulic valve lifters, but just in case its not, does anyone have any ideas as to what else it could be?

The smaller clicking sound gets much louder as the RPMs go higher, and at idle the car drops RPMs to around 500 and shoots quickly back up to 1000. Also, this sound is accompanied by another strange clicking sound that is louder than the first but goes off at a seemingly faster rate and makes the engine sound like a helicopter.

Could this just be a dirty throttle body?

What else could that be?

1 Answer 1


How much Marvel's did you put in your oil? Realize that the Marvel's will thin your oil out, clean up any sludge, and shouldn't be run for any real length of time after you put it in (should put it in for a few miles before you change it out, if used at all). If you still haven't changed out the oil, I'd highly suggest you get just plain oil into your Stang and see if the noise is still there. More than likely the Marvel's is causing the oil to be thinner which in turn is causing the extra noises you're talking about.

  • Thanks for the quick response. And yes I will change the oil once everything gets cleaned out...about how long should I keep the Marvel's in the engine?
    – Miguel M.
    Dec 31, 2016 at 20:12
  • @MiguelM. - I couldn't tell you for sure, but I wouldn't keep it in there more than 50 miles. If there is sludge in your engine the Marvel's will clean it out and it will all get deposited in your filter, which could cause it to bypass and you'd have unfiltered oil running through your engine. It should clean things up really well, but it's not something you want to leave in there for very long. Dec 31, 2016 at 20:15
  • Ok thanks. Do you know of anything else that could be causing the noise? I heard that it could be the lifters or the rod? And I read that a dirty throttle body could be causing the rpm drop. The noise sounds as if it is coming from the left side on the top of it.
    – Miguel M.
    Dec 31, 2016 at 20:21
  • Who knows with the Marvel's in there. What I'm suggesting is listen for the noise once the Marvel's is out and good oil is back. Then you can make an assessment as to whether it's a good noise or a bad noise. If you want to get the oil changed out, listen for the difference, then post back up here with the results, we can probably help you further. Dec 31, 2016 at 20:22
  • I will definetly post back here when I do. Thank you very much.
    – Miguel M.
    Dec 31, 2016 at 20:26

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