HELP! Sudden loud ticking only during coldstart and driving
 

*Youtube link to ticking video below*

Hello all, I've had my '09 370z 7AT for 9 months now with minimal issues until I thought I noticed a small tick when I pulled in the driveway the other day. I put the car in park and revved it a bit and didn't hear anything so I figured it was nothing. The next day I started the car and there was a very loud ticking sound coming from the engine bay (I've always had the classic slight z valve tick sound and this is way louder and only on the passenger side). I popped the hood and listened and the ticking is coming from somewhere right around the throttle body/valve cover on the passenger side, definitely not deep in the engine. After the car went out of "start up/choke mode" and the rpms dropped from 1500 or so to the standard 700, the ticking went away. That is until I started driving and the tick sound came back loudly, increasing and decreasing in sync with the rpms. I returned home and parked the car and the ticking went away again even with revs. When I started it again this morning to take the attached video the tick was loud as ever. I'm due for an oil change, (almost 6k miles with full synthetic), but the oil level is right where it should be and does not look too dirty. This is a sudden occurring problem, not a slow onset one. I definitely drive my car "with spirit" but nothing too excessive. Attached is a video of the ticking sound right after start up. You can hear at the end I rev the car and it seems to go away and then returns after. Only other thing I can think to mention is that the trans has been slipping a bit only on 4th-5th under hard acceleration. I heard this is a fairly common issue with the 7AT 370z when the fluid gets burnt out. I have new fluid, just haven't gotten around to changing it yet. With that being said, I don't believe the 2 issues are related, just thought I'd throw it out there.

Note* I had issues attaching the video, I instead posted it on Youtube, here is the link to the video:

https://youtu.be/RCvkfT5XJhs

Any help would be appreciated. Thanks
~Evan

This is your problem. Oil change intervals are 3750 miles, even less if you run E85. I hope you haven't hurt your engine.

Someone more mechanically inclined than me will chime in for you. Definitely does not sound good.

Thanks for the response. This is my first time hearing 3750 miles but I found some other people saying it as well. Dealership told me they put full synthetic in it and said I was due for a change at 95,500 miles (5000 after change). It's at about 96,400 now. Id be shocked if the motor broke cause I went a few miles over Nissan's recommended oil change time frame but who knows. With that being said, the noise is clearly coming from something in/near the passenger side valve cover or throttle body, not anything deep inside that would usually give out due to low/old oil like the bearings. my guess would be a pushrod, lifter, or rocker arm. I don't believe any of these problems would be caused from a slightly late oil change.

I don't think it'd be an issue with full synthetic oil for 6k miles. does the car/engine run normally with that noise.

sounds like some kind of exhaust leak.... any exhaust work done on the car?

This engine doesn't have pushrods or anything of that nature. The camshaft pushes on a shimmed cam bucket that sits on top of the valve/valve spring.

I agree with nis350, check for exhaust leaks.

I'm going off the sound in a Youtube video so take this with a grain of salt: sounds like an exhaust leak to me.

Get a length of garden hose or similar. Put one end to your ear and move the other end around the manifold, exhaust pipe, and engine compartment to find the source of the noise. Keep the hose, your hair, clothing, etc away from moving parts.

It seems to run normally, it has a Greddy catback exhaust and Megan Racing (I believe) headers. Both were installed by the previous owner and have given me no problems thus far. Sound definitely seems to be coming from the throttle body or right below it but could be coming from a gap between the header and the block and echoing up. Ill check it out. Thanks

Ill try that, Thanks

It's an 09. They are the worst engines. We have had a couple of folks on here loose an engine on that year model for little reason at all. I hope it is not, but it is possible. His issue may be due to galley gaskets are blown out. An oil pressure check with a gauge will be needed to diagnose further.

From the video it sounds like you have an exhaust leak. Get a flashlight and look around the exhaust manifold for black marks where the exhaust manifold bolts to the cylinder head and check for cracks. A stud could have broken off. If you can take off the exhaust manifolds heat shield you should do so you can get a better view. I would also check where the exhaust manifold bolts to the cat.

the noise is definitely external rather than internal like a rod knock. I'd focus on the exhaust area based on the nature of the noise - exhaust manifold gasket?

It sounds like a collapsed lifter. I would try Lucas low viscosity oil stabilizer. Back in the day we would substitute a quart of Rislone or AT fluid with an oil change. The idea is to get the collapsed lifter clean so it will pump up. Do NOT run this very long or hard! 500 miles maybe. Follow the additive manufacture’s instructions. I have had great luck with Lucas products. Nvlitedude

Ya, sounds like exhaust. Goes away when everything heats up and expands.

zz

Welp, many of ya'll were right! whoever installed the aftermarket headers before I purchased the car didn't torque the bolts down and cross threaded half of the lug holes in the head. Thankfully I was able to fit a tap in and carefully retap the beginning of the threads in order to find the original thread passage. Got it all back together and the tick is gone. Thanks!