I have a 2005 G35x with 160k miles on it.. I have noticed over the last month that when I'm sitting with the windows down at a stop in Drive, I hear a slight knocking coming from my engine.. my car runs fine and hasn't had any issues in 5 years should I worry? and yes my oil is synthetic and I check it every couple days never Low! anybody get this knocking sound?

 

Can you hear it when you're driving? Does it get faster as the motor revs? Not a lot of issues will cause a knocking in the motor other than a piston rod going bad, hope that isn't your issue.

 

I don't hear is when I'm drivin or when I rev.. just when its idling in drive when the revs drop a lil.

 

My friend had this issue, the engine said good by at 180k.

 

yah, it's just barely noticeable and I use good synthetic oil and change it on time.. kinda sucks I hope it doesn't get louder.. what happened to your friend's engine?

 

It may be the fuel dampener. There is a TSB I beleive

http://my350z.com/forum/maintenance-...amper-tsb.html

 

That knock you hear isnt good but its actually pretty common with the vq35 in g35/350z.Thats is most likely your lifter valve,you can hear it on idle but when you accelerate you wont hear it because of the rpms going up,turn your motor on open the oil cap for a second and if you hear it louder then its definatley your lifter valve had same problem in my old 350z.

check these things out

oil viscosity if your not running 5w30 that could be the issue
g35 lifter valve is self adjusting so if there is built up gunk then it wont be able to properly self adjust therefore it will stay slightly open and make a tapping noise

try adding a qt of oil addkitive to free up your lifters if that doesnt work then you have a choice,either change motor or check with your local dealetr if they can change it for you.


hope this helps.

 

that helps a lot as you have describe what I was trying to! my car is way beyond bring to the dealer to replace as i'm at 162k miles.. I'll try the additive but otherwise what will happen if it gets worse? like driving-wise?

 

My 05 also started knocking and sounding like a diesel engine after my first oil change when I bought it used with 40K. Brought it into the dealer and it ended up being that a connecting rod broke off the crankshaft. Luckily I was covered under warranty and got the long block replaced at no charge. Hopefully this isn't your situation but just wanted to give you another possibility of what it could be.

 

My motor is finally giving up on me too. It was making bad ticking noise for a while and not its misfiring. Time to get a new motor in.

 

Did you check your spark plugs? I've heard of engines causing a tick, and when the owner checked, it turns out the spark plug had started to back out of the head from not being torqued properly.

 

ok glad that helped.i read somewhere on here a post about a guy with the same issue and 20k later his car is still running just fine but with the tapping noise..i would take it to a good mechanic and see what options you have