engine knock

[BrokenTsi]

so I was driving one day, and my engine made an awful noise de-accelerating. so i pulled over and shut the engine off.

Started it back up, and there was no noise. Car runs GREAT at idle. Good oil pressure too.

The knock isn't consistent. Never does it at idle, only higher rpms. And even if I hold it at 2500, the noise is barely there, but when the engine de-accelerates, it makes that awful noise. I've had a rod/main bearing go before and it sounds very similar, yet this time it isnt consistent.

So I checked the timing marks and they all line up except the rear balance shaft/oil pump gear. I re-timed it, and as soon as the car started over, I heard it jump and it knocked really loud. Checked the timing, and it the oil pump gear was WAY off.

My car has a new timing tensioner and belt too. I pulled the oil pan, NO metal shavings and no loose rod caps or anything. Oil is just fine, nothing in the pan or the sump.

Right now Im in the middle of doing a bshaft removal. Anybody ever have this problem?

 

[luv2rallye]

Remember the rear balance shaft has to be on the correct revolution (1 rev is correct and the next rev is incorrect). Just a thought but have you checked your motor mounts?

 

[BrokenTsi]

its not motor mounts, mine are solid prothane.

Ive seen rear balance shafts go out of phase and make a noise, but not like this. Its down right horrific.

Im almost done removing the balance shafts. I'll let you know how it goes.

 

[cramec2]

You may have spun a connecting rod bearing..Mine had the same shi_ happen..

 

[BrokenTsi]

nope, didn't spin a connecting rod bearing. Made sure of that tonite. If I did spin one, I woudln't have oil pressure and there would be metal shavings all over the place, and the motor is clean as can be. And there is no play in the bearings as well.

It appears that there was a problem with the balance shafts, so I removed them, just gotta put on my oil pan and timing belt now.

I'm still skeptical about the bshafts, the silent shaft sprocket was on finger loose for some reason (previous owner), that may have caused the knock, but I cant figure out why the oil pump gear would be jumping and always be off the timing mark.

 

[Spoolin4Ever]

Let us know what happens after you fire her up, bro.

 

[BrokenTsi]

welp, after removing the balance shafts, and tearing my motor completely apart, the motor still knocked.

But this time, the knock changed when the clutch pedal was pushed in. So I pulled the trans and found a flywheel bolt had backed out. I have no idea how it did, but it did.

Sure did fool me, I was about to pull the motor and build myself a sick block and run 10's.

I hate removing balance shafts and transmissions.