My car, '05 OBXT has developed a nasty tick/clatter and I've been unable to figure out what the problem is. The car is stock, excepting for a custom 3" inch mid pipe with straight through resonator. The car starts and idles fine and has no CELs. The noise occurs when idling, and while it will go up with rpm, the frequency isn't in direct proportion to rpm. While the noise seems to be coming from the top rear passenger side of the engine (we were thinking turbo), it has defied isolation with a stethoscope. The sound becomes a clatter when the engine is revved. The noise appeared within 50 miles of having an oil/filter change and having colder plugs put in preparation for getting Stage 3 mods. At the same time the car developed a hesitancy to develop boost. Off idle the car will clearly be off boost and then suddenly inconsistently begin to develop boost. Acts like the wastegate is stuck open and then unsticking. The oil level is fine. The oil filter was replaced to ensure that there wasn't a problem with the check valve in the filter. The inline oil filters are gone. The timing belt was checked and found to be loose due to a seized tensioner, but the timing was spot on and the belt was in good condition. Replacing the tensioner had no effect. Today, we got closer to finding the problem, but still can't figure it out. Oil pressure was checked today and found to be 75psi at cold idle, but when the noise occurs the pressure drops to 70psi. Was kind of thinking the wastegate was sticking open and unsticking and that was the sound, but was unable to isolate the sound to the wastegate. Next thought was rod knock from the oil pickup tube beginning to fail and this still hasn't been ruled out, but the oil pressure seems too high for this to be the problem. Video with sound of the engine cold Video with sound of the engine warm I've got a Tactrix cable on the way, but in the meantime, anybody got any idea about what the problem(s) could be? TIA Ray
I don't know, but watching that second video, with teh slowed down clatter, I almost want to say it might be up by the belts. It doesn't appear to be ticking with the rotation of the motor at all, it feels more on par with those belts. Hard to say. Also agree with Nuke, I'd get a proper mechanic with a stetho on it.
i agree that it sounds more like a belt or something making contact with something. internet diagnostics at its finest from me. but i would third the take it in to someone.
The car has been at my mechanic's for a couple of weeks. We have not been able to definitively figure out the source of the noise. Doesn't quite sound or act like a rod knock in either of our opinions. Up on a rack or on the ground we haven't been able to get a fix on it with a stethoscope. The noise sounds high pitched and more valve train like than the deeper knock you get from rods to both of us. We found the seized timing belt tensioner looking for sources of the sound from the front of the engine, but that didn't do the trick. Suspected the AVCS cam sprockets, but no CEL. Any way these can go bad and not generate a code? Any way a problem with the Tumbler Generator Valve system could be the source? Any other ideas? Ray
It doesn't sound like an engine noise to me, sounds like something hitting a plastic belt guard or something. However, I'm no professional...
That sounds like a rod to me, but the oil pressure dealy doesnt make sense. So the timing belt tensioner has been replaced? Ive heard timing belt tensioners make this noise.
Just sent you a PM, however after listening to the second video... watch the belt on the left, as it goes around everytime you hear the sound and you can see that white line go by???
Qtip those ears man... not even close one sounds like a pellet bouncing around in a can the other sounds like someone banging a metal pail with a 3lb hammer... Unless the sound quality is that bad in Rays video... Gonna try to stop by and get a listen for myself...
well when my rod bearing went out it sounded more like this!..... this video gives me chillshnoes: [YOUTUBE]http://www.youtube.com/watch?v=VEIUDRDllOI&NR=1[/YOUTUBE] I'm still having nightmares of that sound
read some of the posts to this video. the guy said it was a loose spark plug, I know it doesn't sound quite the same but might be something to look at......:dunno:
Yep. Best way I've found to do this (from experience) is to go to Target or Menards or whatever, and get yourself the cheapest clear plastic 5+ quart container you can find, one of those storage types. They are usually about 3-5 bucks. Drain your oil into it, drain your filter into it. Then like Matt said, cut the filter open with some tin snips, DON'T USE A DIE GRINDER OR ANYTHING THAT IS GOING TO LEAVE A METALLIC MESS. More than likely you can just rip it open with a flathead screwdriver and some elbow grease, but I don't like to fuss around like that. Once you drain your oil into that clear bin, get yourself a flashlight, if your oil looks like one of those sparkly lava lamps, you've got problems. Also, you'll find the same sparkle business on your oil filter element.
Anyone want a side job? And the verdict is........most likely bottom end knock. The pleats of the cut apart oil filter unfortunately have the glint that makes gold miners happy and gearheads sad. Next up, rebuild or replace? Anyone want a side job?
