Hey guys i have a 03 Track Edition 350z. Lately i have been noticing when i start my car.. (only when the car hasnt been run for a few hours) the rpms jump up (as it should when you start a car) but when it reaches its peak theres a rattling noise coming from the front of the car.. The rpms go back down and if i rev my motor the sound is gone... if i then turn the car off and start it back up.. no noise..

My thinking.. maybe there isnt enough oil getting to the valves before it starts (Since it only does it when the car has sat for a while) and the oil has time to drain down to the sump..

Any imput would be great... or past expriences with this problem..

Thanks in advance!

Dave

P.S. i also checked my oil level.. and it appears to be fine....

 

I have the same thing happen. It usually happens when I wiggle the shifter as it's staring up. So I make sure the car is in neutral before I start it up and not move it during start up. I think it's something in the flywheel or clutch.

 

Same here. Sometimes it sounds like someone's shooting an AK47

 

you know i never though about it being something in the tranny... my WRX had the same thing happen after i put a light weight flywheel in it... How come it only does it sometimes.... unexplainable...? haha

 

if it any different from the usually rattle (it also happens when turning off the car) it could be a busted motor mount. i went through 8 motor mounts on my civic in 2 years. thats why i stopped powershifting :X

 

Its the tranny! its normal! mines does it too.. 03 track Le manz...

 

mine only does it on the start up.. when it hasnt been run for a while and doesnt rattle when i turn it off.. so i am thinking its a different one that you... also it sounds like its either in the motor.. or now starting to think tranny...

 

Mine does it as well. 03 touring automatic. Only does it if engine is completely cold though.

 

Same here Peterpit, only on very first start of the day, mine's an 04, tiptronic. Quite a loud rattling and will generally happen for about 5-10 seconds then stops, and it definitely sounds like it's coming from the engine bay, underneath. Dealer replaced the left bank solenoid as that's what they thought it was, still doing it, so I guess they weren't correct.

I had a airconditioning housing in my 200sx that made a similar nasty rattle, but that was constant, so probably not that.

 

well its almost kind of comforting to know others are having the same thing happen... i noticed tonight when i left work (after the car sitting for 7 hours in 35 degree) weather it didnt make the noise when i first took the car out of first and into neutral then cranked.. not sure if it was just a fluke or what not.. but ill report tomorrow when i get to work!

Dave

 

Very difficult to diagnose sounds on the internet. Is this a value tapping? Mileage?

 

Watch the oil pressure gauge or the light and let us know how long it makes this noise after the light goes out. Almost sounds like excessive bearing clearance.

 

Same here. Took it to the Nissan dealer but they could not hear anything. Guess it's normal.

 

For me the rattle is only for like 2 seconds and it goes away. Not overly concerned about it.

 

Can someone please elaborate more on the issue. Some of you claim it's the transmission. Is this a problem on both the 6M and 5A. Mine is an auto but the sound seems to be coming from the engine.

This sound really makes the Z sound like crap on start up.

 

The VQ has a hydraulic tensioner (oil pressure driven)for the timing chain. With the lack of oil pressure at start up the chain makes a clacking sound in the front timing cover. It's normal. My 01 Maxima did it and my 03.5 G35 did it as well. No worries.

 

Guess I would have to live with it.

 

Mine does the fast rapping/tapping sound from the front of the car too, on cold starts.

I figured the same thing, not enough oil pressure at startup.

If my engine seizes, I'll get a new engine. I'm not too worried about it.