ColdFusion

iTrader: (2)

Hi all, so not sure if some of you remember but I had a severe engine repair done to my '06 IS350 a while back. The main crankshaft bearings were replaced due to severe wear and metal flanks during my oil changes. It has since been around 2k miles since that repair was done, but recently a few new noises popped up and they have me worried. You can hear two of them below in the video I posted. I would like some insight to figure out what exactly is causing them.


First off, my original engine problem came from a rev-dependent ticking noise. This noise currently sounds similar (which is why I'm so worried), however it is much softer and seems to only exist around the 1.5-2k RPM range.

1. I am worried about the serpentine belt and possibly the belt tensioner. I don't stare at this part often enough, but the pulley shaking while idling was sort of worrying. Is the bolt on there not tight enough, or is the bearing under the tensioner pully actually failing?

2. The second noise has been around a bit longer (actually at the same time as the original crank bearing sound), and it seems to originate from the spark plugs/coilpacks. No engine or error codes are being thrown by the car, so I don't know if this sound is normal coil pack firing, or something's going wrong that the car can't detect. The spark plugs are brand new, just under 2.5k miles with them.

3. The third noise I can't hear while the engine is idle, but ever since I installed the F-Sport Intake, whenever I rev the engine I hear a very high pitch whooshing/whining noise. I think it sounds like air escaping from somewhere, so I couldn't tell if it was a vacuum or intake hose leak somewhere. Did I miss something while installing the intake upgrade?

Thanks for all the help

SeanO

iTrader: (1)

1. A stethoscope or long screwdriver put on the end of the bolt against your ear will give you a good listen in on the bearings - you can check the bolt for tightness but it does kind of sound like it could be a bad bearing.

2. possibly a timing issue?

3. The intake box has the hole in the side as I'm sure you know so it could just be the sound of air sucking into the box - maybe check the gear clamps on both ends to make sure they're tight but i doubt these would be the issue - there ain't much more to it then that

ColdFusion

iTrader: (2)

1. I'll do this when I get home, thanks. What kind of sound would indicate failing bearings?

2. Oh god I hope not. Any way to check for problems through this?

3. I recall that hole on the side that wasn't connected to anything. Would the whooshing sound be that loud though? I'll check the clamps tonight as well too.

SeanO

iTrader: (1)

1. It will sound "chunky" - a good bearing should produce a constant "smooth" rolling sound - move your screwdriver around on different bolts and you should notice slight differences - be careful obviously - I had an old grand prix GTP that had a supercharger pulley needed replacing and listening to that through a stethoscope you could tell instantly the bearing was shot

2. Maybe hooking up a scanner but I'm not too sure to be honest

3. Yeah the whooshing sound can be loud - a lot of people love to hear that sound haha myself included - I have F sport intake as well - if its a whistling sound then there could be an air leak somewhere but that's unlikely

Gville350

iTrader: (10)

Though I've not done this on any late model car, I've been known to remove the spark plug wire to a cylinder to see if the noise goes away in that cylinder. If it does, then more than likely it's a bearing...rod bearing.