Mysterious SR20DET VCT Head noise.

[nichthen]

There is a ticking noise coming from what seems like the top of the motor, its driving me absolutely nuts trying to find out the solution. It does not affect performance and it only happens between 800-1100 RPM only, sometimes it completely goes away and sometimes its very loud.

I know this has been covered 1000 times over the years, but I've searched the internet far and wide and tried the obvious solutions to no avail.

With each step i've done, i've re-assembled and checked to see if it's still there.

I've tried:
- Brand new S15 timing chain tensioner
- Removed, inspected and re-bleed all lifters, they move easily in and out as they should
- Inspected all cam shims/the head in general for anything suspicious
- Double checked that the engine is timed correctly.
- Double checked all cam caps, bolts and torqued them down correctly
- Removed the Top timing chain guide, the one under the rocket cover (that nissan even says to take off)
- Changed oil
- Checked compression (all between 140-150)


I Don't know what else could be going wrong, the chain itself doesn't seem to have an excess of slack in it, not enough that it would be physically hitting on anything.

If anybody could point me in the right direction, i would really really appreciate it.

Here is a video of the noise at its worst. https://www.youtube.com/watch?v=5PMojND0F8M

thank you

[S14rebuild]

Ummm vtc cam gear and actuator...

[icedsole]

Sounds like the VTC gear and solenoid are starting to go bad

[nichthen]

Ummm vtc cam gear and actuator...

Sounds like the VTC gear and solenoid are starting to go bad

I did unplug the VTC solenoid and the noise was still there.

What if thats not the issue, would you recommend me do anything else?

[icedsole]

I did unplug the VTC solenoid and the noise was still there.

What if thats not the issue, would you recommend me do anything else?

Im not sure that is the best way of testing it because if the gear on the cam its self is bad internally its going to make a noise no matter what?

I would guess the solenoid is still good since unplugging made no difference. Sounds like you have checked everything else so the gear would be the last thing to replace and is a pretty common issue for them to go bad.

[jedi03]

would suggest use stethoscope to locate exactly where noise is and go from there...a lot of parts have been thrown at this and sounds like still not corrected...

[Kingtal0n]

Sounds like VTC isn't coming on.

If you unplug the VTC or if the solenoid stops working for whatever reason (broken wire/clip or just bad)
All the oil drains out of the VTC gear and it will sound like that.

It won't stop until you either
1. turn on vtc (1 wire I think gets a ground from the ecu but you can manually ground it, I used to have mine on a switch)
2. replace the vtc gear with the S13 gear eliminate VTC (don't recommend this)