Strange sound issue? What could it be...

[Maxthepersonz]

I just saw another DSMr on here CrackedDSM I beleive post a thread with a video of his car sounding strange. I think mine has a similar sound but in my case it is sort of odd... Not sure If this should be in the AT thread or elsewhere because it was a crank pulley problem as well.

I finally got my car up and running, tuned it to 21 PSI safely before cranking it up higher. I start to hear this strange noise while I'm decelerating one time after 5 or so pulls with the car. I assume it's something really bad from the sound but when I got home I discovered the long bolt you can use to turn the crank over had completely backed itself out of the harmonic balancer on the crank. I removed the bolt, red loctitied it, and torqued it to spec back in its place.

While doing this I also checked my flexplate bolts because that was my first assumption. I'm running a Kiggly flexplate by the way. 2 of them had backed out just a tiny bit and they were all red loctited when I installed them. I tightened those as well.
WHAT'S THE BEST WAY TO TORQUE THESE TO SPEC? EXACT TOOLS?

Took the car out and it drove totally fine again. No weird noises or anything until after a few pulls and probably 50 miles of driving. This time however the bolt in the balancer didn't loosen itself up and I still had a strange sound. This sound did go away just from tightening this bolt before so I have no idea what it could be!

Just to add. The car only ever seemeed to make this noise at lower rpms while decelerating and not all of the time at all. It was like an on and off thing that kind of slowly got worse. There was one time that I never heard the noise at all, car was turned off but then as soon as I turned it on it was very bad but then went away after driving past 1-3MPH and then only did it while decelerating sometimes, not at idle like it did when I first started it up!? What the heck is going on here I've been looking at this thing for hours totally stumped!

I ordered a fluidamper and ARP hardware for the car just now because why not.

 

[Dsmkauai]

Did you Check your timing? That main bolt holds the crank timing sprocket against the oil case, which your timing belt is around. Having that come loose could really cause issues. I would not have loctite that crank bolt only needs to be torqued to spec. Hope it's not a pain to get out if needed. I would check the harmonic balance of its oem to see if it's separated. We need a video of the problem bro. No one will know without it and can only speculate and guess . I would be alittle concerned and wondering what other bolts are coming loose or have fallen out .

 

[CrackedDSM]

x2 to what Dsmkauai said. Get a video of the problem and the sound. My first instinct is to tell you to check your flexplate and pilot bushing. This isn't a "jdm" motor is it?

 

[Maxthepersonz]

Did you Check your timing? That main bolt holds the crank timing sprocket against the oil case, which your timing belt is around. Having that come loose could really cause issues. I would not have loctite that crank bolt only needs to be torqued to spec. Hope it's not a pain to get out if needed. I would check the harmonic balance of its oem to see if it's separated. We need a video of the problem bro. No one will know without it and can only speculate and guess . I would be alittle concerned and wondering what other bolts are coming loose or have fallen out .

Honestly I just finished the car a few days ago. Has been mechanically sound besides this. No leaks at all from anything after basically bolting everything new onto the motor so I don't think I did that bad

I have never even lossened this bolt before which is why it's such a strange issue. I can tell you my cam gears are spot on for timing, but I'll go remove the covers now and see what's going on. Obviously I'll remove the pulley and check for separation before I do that. Thanks for the input guys I'll let you know what I find, if not I'll post a video.

 

[Maxthepersonz]

Pulley is all one piece. Hmmm...

 

[Maxthepersonz]

I got a Fluidampner and re torqued all me flex plate bolts again. Car has been super solid for a few weeks now. No issues.