broken balance shaft?

[regulator213]

When i bought my car it had a weird vibration/noise around 3K RPM. More noise than vibration but my buddy said that my balance shaft belt needed to be replaced. Well i drove the car and the belt ended up snapping. Today replaced the belt and the Tbelt and im still getting that annoying noise/rattle. You cant feel it in the car but you can def hear it when reving in neutral. Possibly a bent or broken balance shaft?

 

[Bohrn]

I would guess not as there would be more noise/carnage if one of them was actually broken.

Recheck all your timing marks and make sure that the rear shaft is "in phase" because the marks can be lined up and still the rear shaft can be out 1 full turn.

Check the VFAQ for more detailed information.

 

[95blackGsTurbo]

In any case you should not be driving the car until you get the problem resolved. I would start by remove the front case and removing the balance shafts to see if either of them are scored or the bearings are going out. At this time you can do an elimination kit as well just to cover your basis. Since you will have the pan off check it for any metallic shavings of debris in it and clean the pickup tube. A weak hydraulic tensioner can also cause this as the arm will just bounce off of it. Be sure to check it and all of the pulleys as well. You will probably find some worn parts in there.
http://vfaq.com/mods/timingbelt-2G.html
http://vfaq.com/mods/balance-shafts.html

 

[regulator213]

Ok here is what I have found, yes the rear balance shaft is in phase ( I checked and rechecked to make sure this wasnt the problem) and again there is no vibration in the car while driving. The front balance shaft is fine, this is not the problem. I believe the noise is coming from under the valve cover after looking into it more closely. What under the valve cover could be loose or bad that would cause such a bad rattling noise? I will try to get a video up when i get a chance. The other thing is that it starts at around 3000 RPM and doesn't stop. Although i have only rev'ed it to around 4K

 

[95blackGsTurbo]

Check to see if a valve spring is cracked or a rocker is broken/off.

 

[regulator213]

Sounds good. Will do, thank you sir.

 

[regulator213]

well there definitely nothing obvious that stands out when i took of the valve cover. I think im gonna take her down to Extreme PSI and see if they have any ideas. Hopefully they do.

 

[whe3ls]

oil pump out of phase?

 

[regulator213]

Naa its definitely coming from the valve train. You can hear it pretty well on top of the engine and again the car doesnt vibrate like the shafts are out of phase. Its just a noise coming from under the valve cover.

 

[regulator213]

Is there a possibility that the lifters are going out and they cant expand and contract fast enough to keep up with high RPM's?

 

[big_d]

Post up a video.

 

[Jarnutt]

Im having the same exact issue. If you rev the engine by hand under the hood, at about 3k RPMs it starts to make a rattling noise near the rear of the valve cover, almost like a worn out bearing or something. I have no metal in my oil after 3k miles of it, and it has me a bit confused. It doesnt shake the motor, motor purrs like a kitten and revs smooth aside from that noise, its the worst when my motor is cold, and gets quieter as it warms up.

 

[regulator213]

i'll post a video in a bit. I pulled the plugs off each of the cylinders and the noise got worse. I changed the oil and it was a little sparkly but not much. I re-torqued the camshaft bearing caps and checked them for wear or scoring and they were all fine. what else?

YouTube - valve clatter?

Here is a video of my engine up close at idle. I used the screwdriver stethescope method and i think the noise is coming from my injectors. Listen 4 seconds into the video till about 8 seconds. Could this have anything to do with the noise?

YouTube - up close idle, loud injectors?

 

[Jarnutt]

that sounds like injector tick, but hard to say, it distorts a bit. not the same sound Im hearing from mine, mines more of an instantly gets loud at a certain RPM, your noise seems linear with RPM

 

[regulator213]

what causes injector tick? the other thing is that mine gets loud right at 2800 rpm, you cant even hear it at idle. Sorry for the bad audio, it was a phone vid.

 

[Jarnutt]

Sorry, it sounded like it was also doing it at idle, if it starts at 2800k RPM then its probably not injectors ticking. Lots of things cause injector ticks, age, contaminants in fuel, or just the nature of the beast. I don't know what kind of injectors these cars run, some cars run a disc type, others are needle and seat, I've owned some loud ass injectors in my cars over the years, needle type have been the loudest, at least in my buick and my civic for that matter, but its just as loud at idle as revved up, it just speeds up the ticking noise to match.

 

[regulator213]

gotcha

 

[Jarnutt]

throw some plastic cling wrap over the valves and run it without the valve cover off, Ive done that before, its ghetto as hell but it helped me find out I had a collapsed lifter

 

[regulator213]

hahaha very funny but true as well. good call

 

[regulator213]

would my base timing being off cause a noise like this?

 

[Jarnutt]

I have no idea about that, base timing could cause misfires if it was off enough, but a misfire would be obvious, especially when driving.

 

[talontd92tsi]

If your Cam timing was off it could cause a noise, but your base timing is an ignition based timing system. Has nothing mechanical to do with it besides the sensors operation.

 

[regulator213]

when you say cam timing do you mean lining up the timing belt? or do you mean the position of the Cam angle sensor?

 

[JTURBOGSX]

im also experiencing same exact problem! has anybody figured it out yet

 

[whe3ls]

i'll post a video in a bit. I pulled the plugs off each of the cylinders and the noise got worse. I changed the oil and it was a little sparkly but not much. I re-torqued the camshaft bearing caps and checked them for wear or scoring and they were all fine. what else?

YouTube - valve clatter?

Here is a video of my engine up close at idle. I used the screwdriver stethescope method and i think the noise is coming from my injectors. Listen 4 seconds into the video till about 8 seconds. Could this have anything to do with the noise?

YouTube - up close idle, loud injectors?

in the video's it almost sounds liek the valves are hitting the pistons. id also check the check for play back and forth, and compression test would also help