[marsosporsche]

Hi, i took the car for a drive today and without notice, it started doing a loud "TAC TAC" noise very loud, sound to me maybe like a valve??, and also felt that i had lost some power and the car will not idle anymore. The "TAC TAC" noise is not something that i could time, like for example every engine cycle, only when i press the throttle and louder when driving compare to parked.
I'll try to upload a video if i can.

Please any reflection are welcome and hope that one of you guys can guide me on what to check.

Thank you

Adrien

[marsosporsche]

YouTube - ‪Video from My Phone‬‏

YouTube - ‪Video from My Phone‬‏

[VaSteve]

Chain tensioner?

Just a guess since it would be more in time with the engine if a broken stud.

[tdatk]

Eeeeek.....sounds like it's running on 5 and the 6th rod is broke and bouncing around in there.

[marsosporsche]

Piston rode?

[tdatk]

Do a quick check by pulling and replacing 1 plug wire at a time until there is no change in rpm, that would be the offending cylinder. you would then pull the spark plug and insert a long straw in that cylinder, then turn the engine over by hand while observing if the straw moves...

Normally wouldn't run an engine that sounds like that, but I think the damage is already done, call my cell if you like.
540-247-3587

[Vicegrip]

My computer does not want to play the sound. Valve adjusters have been known come loose and go to big valve lash. Tap tap and down on power. Just a WAG.

Just heard the sound. Shut the car off for Dog's sake. Odd sound. Is sound easily identified as coming from inside the motor? Is there something external to the motor flapping? Clutch in and out change anything? Loud front of or rear of motor, right or left? Steve's chain tensioner or perhaps a chain ramp might be in the right direction.

[smdubovsky]

Wow, that noise has me stumped since its not directly related to RPM. Sure sounds like something is loose/rattling around though. Maybe a broken rocker is rattling around?? I'd start w/ the simple stuff. Drain oil and look for bits, pull valve covers and look for bits, etc. If those turn up zilch a compression test will narrow down to the offending cylinder.

[marsosporsche]

Thank you all ,
sound is coming from passenger side and when gear engage sound is louder when forcing

[OldTee]

Haven't hooked up speakers yet since my move. Maybe soon, so the following is pure speculation. One thing that will make noise like you heard is a rocker adjuster nut fell off and the rocker is way out of adjustment. Don't drive it. If you do you own work pull the valve covers and inspect each rocker carefully. Replace nut (it will be in one of the lower valve covers, readjust the valve and go drive. If you must have it flat bedded to Matt at Stuttgart Performance Engineering (301) 948-6762. He will give you an honest evaluation.

ARF