Let me guess, 6MT? Your engine has a slight misfire at idle (mine always has, since it was brand new) and it sends a slight vibration through the transmission and makes a clunking sound each time.

Simple test - does it go away or become less noticable if you hold the clutch in?

 

i think mine does yes

 

does your idle flutter up and down?? and is your oil gauge below 1/4 line while engine is fluttering?? and does your shifter vibrate as well while everything is happening simultaneously??

 

idle flutter up and down, yes after its warmed up, not when cold. no poping when cold either though.

oil gauge below 1/4 line, yes, told it was normal

shifter vibrate, yes, i was told this was normal in all Zeds though.

 

I noticed the small pops after installing the ingen CAI. Pretty sure a tune would smooth this right out. AFR most likely is not quite right.

 

so i took the car to the dealer, they said its a intake cam, or throttle body adjusting. They said it sounds louder because the sound is being amplified by the aftermarket intake. I was told they have heard it on other cars before and its nothing to worry about. its on record now so.............

anyone else gone to the dealer?

 

Mine has these symptoms as described in this topic too. I was kind of worried, well, maybe not worried, but i am curious to know what it is. After a short run to work etc, if i let the engine idle in neutral for maybe 30secs, i can hear the exhaust note pop occaisionally, and also feel/hear a slight knock come from somewhere intermitently, my first thought was misfire, but the rpm's do not fluctuate at all....it is a strange one.

 

Its ok. When u upgrade ur exhaust it flows more so there for ur valve are workin fast than normal. Its not really a pop its more like a lope. All cars with aftermarket exhaust do this. Ur str8

 

Needs more plenum spacers.

 

Mine does it as well when it was stock and now with the aftermarket exhaust on.Its even worse when the A/c is off. The car has a rougher than usual idle in the end I figured it was a normal condition with the engineering of the car so I didn't eve bother with diagnosing it. You've heard the saying "If it isn't broke, don't fix it"

 

mine has the same problem and at one point it threw a code sayin random misfires but soon after it just went away..but it still pops..

 

Mine does it too, it did it when it was bone stock and still does it with CAI & Intake Manifold. The care idles normal and does the poping sound every 10-15 seconds, with the clutch in or out. It doesnt bother me I assumed it was normal considering all the other Z's have rode in do it to. LOL on another note my clutch chatters when it is not pushed in, but I was told that it was normal for the clutch chatter. I say it is what it is My car runs strong and hard so I am going to keep driving the Sh*t out of it, if it ever decides to Sh*t on me then it will gime all the more reason to go a head and do the LSX Swap in it.

 

Hi guys any updates on this issue?

I have this problem after cleaning my throttle body. The idling went very high but was rectified using the relearn procedure but now it pops very often.

Seems like no one could have the answer for this issues.

 

05 350z 6MT. My VQ does the same. I'm a rev up.
700 rpm idle, k&n cold air. No other mods.
If I'm at idle and I give her a rev she pops and gurgles. If I'm in 1st or second and I'm slowing down she does the same.
Has always done it. I changed the spark plugs and did all the relearns. No change.
I used to idle high at about 1000rpm. Still did it the same then.
I'm under the impression it's normal.

 

Similar issue im starting to believe it's normal with age

 

Ive had this since I bought my 04 6mt. Seems to be normal for these cars. Ive convinced myself to let it go since the car has no issues and runs great. Current mileage is 112,000