99 vw Jetta grinding noise from top of motor and engine runs…

HI,

Ok, you will need to remove the valve cover. That sounds like you have either a bad lobe on the camshaft or possible a rocker arm has gotten loose. Definitely something in the valve train

HI,

Ok, listen to the area near the distributor with a mechanic's stethoscope.

HI,

yes, the distributor. A 99 jetta 2L has a distributor. It has a gear on it and if it is the issue, you will have loss of power and will have a cam sensor code since the cam sensor is inside the distributor.

HI,

Ok, can I get the vin number for your vehicle

HI,

Ok, my bad. I looked at the ABA engine and yours is the AEG engine.

you are going to need to pull the timing cover to inspect the cam sensor and the cam sensor trigger wheel. Either the cam sensor end has separated some and hitting the trigger wheel or the trigger wheel has separated from the cam sprocket. SEE ATTACHED

HI,

not necessarily. At idle, if it is the trigger wheel, it the rpms are high enough to have it move enough to cause noise.

the trigger wheel is on the inside of the cam sprocket, but you should be able to put your finger thru the cam sprockets to feel the trigger wheel to see if there is any play or movement in it independent of the cam sprocket.

Hi,

it is rare for this engine for the cam sensor to cause timing to be off to the point to cause the cam lobes and lifters to be out synch enough to cause noise. Possible but rate.

You failed to mention this being a used engine you just installed. There is a possbility of a slightly bent valve. I would do a compression test on the cylinders and see if one is at 100psi or lower, which would point to a bent valve

Hi

Sounds good

HI

it is a sohc

HI,

correct. they are in range.

With not issues showing on inspection the valve train, the trigger wheel or compression test, the only thing left would be the cam sensor. I dont see anything else as the cause

HI,

I am going to see if another expert can help you at this point. Do not reply until another expert replies back, otherwise it locks it to me and prevents another expert from helping.

Good luck in getting this resolved

I can't express strongly enough how bad of an idea this is. However, it's completely up to you, obviously.

I'm going to link a video showing exactly where both crank and cam need to be set to, since trying to describe the flywheel mark is impossible. The video will open a few minutes in, and start with setting the cam sprocket properly, and move on from there.https://youtu.be/_8LPnqw2bEk?t=188

I was able to yes. Definitely out of the ordinary on these, and without having the car right in front of me, impossible for me to diagnose.

I'll say that even though this engine is technically an interference engine, it's really rare that AEGs bend valves, unless the belt breaks at some ludicrous RPM.

And yes, I would think that it wouldn't be related to anything in the clutch mechanicals.

Sounds good. Sorry for the delay. Few customers in here over the past hour. And as far as I know, you can reply at any time, even after rating.