I’ll tell the full story from the start, a few months ago I was at an intersection, light turned green and I began to ease into the clutch and moving forward. I noticed a weird rattling/chattering noise coming from the engine. When my foot was slightly going down on the throttle or off the throttle. The noise can be heard from 2k all the way to rev limiter. Even when not driving. Getting home popped the hood and tried having someone rev the engine while I listened to see if something was loose. Couldn’t see anything or think of anything to make this noise. I figured it might be some valve tick. So I did a valve cleaner, replaced gasket covers, spark plugs. The noise still continued. The noise bothered me still for about a month but I couldn’t figure out what was wrong and I didn’t want to throw money at it. One day, being a Z owner I ran it pretty hard down a street and the noise got audibly worse. Do take note. That the engine never drove any different from the noise started nor performed any different. That week I took it to the dealer and they told me it was a timing chain tensioner. I was taken by there diagnosis because I’ve heard a bad loose chain and it didn’t sound like it because the noise was not there while the car was at idle. I ended up listening to the dealer, and I’ve done a chain replacement before so I did it myself. Replaced all the chains, both cam chains and the main chain, replaced all three tensioners, two guides and the crank sprocket. Also replaced water pump while I was in there and every gasket I took off. Also replaced timing cover gaskets again and cleaned up everything also to brand new. Putting it all back together now. The noise is still there, and now the engine when I’m full throttle above 3k seems almost die out a little, it isn’t as peppy anymore and struggles when it higher rpms to build speed. I forgot to note the first time I replaced valve gaskets. The engine did have the same problem feeling kinda sluggish but a code pulled for the timing solenoid not working and I replaced both of them. And the engine felt perfect again, cleared codes and it was all good. There are no codes pulling and the car is driving sluggish again, but I’m hesitant to blame the solenoids again because they got replaced like a month prior. I’m stuck on what could possibly be causing the noise in the engine bay, and why now my car is driving sluggish again. The car is a 2005 350z VQ35 with a little over 150k miles. Take note I do meticulously maintain this car because I do work at a tire shop and I have access to a lot of tool and discounts on parts. Anything that could have been replaced on this car suspension, brakes, and tires wise has been replaced And any engine maintenance has been done regularly. The only engine mod I have done is a PCV delete because I got tired of having to add oil all the time and changing every 2,500k. It’s just a crankcase breather filter on the valve cover and I plugged all the vacuum lines to the intake so no oil can get into the intake. Please help, I’m tired of this noise and I don’t want to retire my Z

Here is a recording of the noise, you can hear it when I bounce the throttle pretty fast