Hello guys,

I am a spanish owner of a 350Z '06 VQ35DE unit.

I have a strange problem in my car and nobody in Spain's forums knows about it.

I wish you can help me about that, and sorry for my bad english.

Since a few days, I have notice what, when the car and engine are hot, noise occurs about 2.000-3.000 rpm when I floor a bump and I am accelerating. It's like a PRRRRRR. Sometimes also the accelerator vibrates with the sound.

If the car is stopped, the engine sounds normal. Occur only if there is movement over an irregular ground.

Its the car is cold, there is no problem.

My 350z has installed MREV2, Plenum Spacer, Megan Exhaust Manifold, Megan Y-pipe, and Kinetix HFC. I use Mobil 1 5W50 and the car has aprox. 30.000 miles.

Greetings and many thanks.

 

I would have to bet on the Flywheel, it actually sounds like the previous owner changed to a lightened flywheel.

 

Hello,

The flywheel is stock. I buy the car with 10.000 miles and the previous owner did not change anything in the car.

I want to comment too that the problem appears in intensive use of the car, for example, 2-3 hours or in a sporty driving. In normal using or few time, there are no symptoms

 

Traction control or ABS kicking in?

 

Hello TheFarmer,

The sound was very similar to the traction control "kicking in", but the ESP and slide lights were OFF.

 

Hello,

Any idea more?

Thanks!

 

possible to post a video?

 

I will try to record one.

Today I used the car and I saw that when the sounds comes, the rpm rise is irregular, like a race car losing traction in acceleration. I'm beginning to be convinced about a damage cluth-flywheel.

 

Sounds to me like your plenum is rubbing against your strut bar due to the spacer you installed. The combination of the heat expanding the metal and torque of accelerating over the bump is causing it to touch and vibrate.

 

You don't notice any lights going off on the dash at the same time do you? After I installed slightly shorter than stock tires on my Z, if I push it too hard on a rough surface, the TCS comes on cause it is sensing a difference in speed from the front to the rear.

 

Apparently, all the screws are pretty tight...



Not, no lights in the dash.

 

It doesn't matter how tight they are...it can still be rubbing. Examine the top of the plenum and see if it shows any marks beneath the STB. You can also simply remove the STB and see if the noise goes away.

 

Hello again.

My mechanic has been testing the car today to found the noise (and vibration in accelerator) and he really doesn't know what is the thing. He says that is not a tranmission or exhaust problem, that's for sure.

Actually, the problem only occurs if the car is really hot (by sporty drive or many hours of use) and I think that is becoming less.

About the plenum, I insert a cloth between strut bar and Plenum to avoid vibrations and test it, like you comment, Zenophile. I will test the car again tomorrow with that.

Thanks again for all your opinions

 

definatly sounds like a clutch issue. by this statement.

 

Blair, if you suspect any clutch slippage, check to make sure there is sufficient free play at the clutch pedal push rod. When the car heats up the clutch master/slave fluid will expand and without some free play it, would start to release spring pressure from the clutch disk.

 

I think that the issue begins two weeks ago. In a travel to Jaen, after 4 hours of highway, I had to go trought a small town, with a lot of steep urban uphills (someone like San Francisco ). I use the cluth and first gear because there were pedestrian on my sides and I went carefully to no cause accidents or damage.

After this I began to listen the noise. But I thought the clutch had not suffered because I did not smell of burning or similar, and the pedal and gear lever feels good like always.

I remember too that I have a "clic" sometimes when I release the clutch pedal but I thought that it was cause by the sensor for the Cruise Control

I hope that if you have damaged the clutch is not permanent damage.

Thanks for your info Jennifer, a lot of thanks.

 

I have installed Megan Headers since a year ago (*sick*). ;Maybe burned gasket or header leak?

Thanks!

 

I have a similar noise. Haven't figured it out yet. It happens after the crest of a hill. mechanical buzz/tapping. I can almost feel it in the floor or pedal. I've adjusted my strut bar with no luck. No visible rubbing there. I thought maybe my sway bar endlinks, or bad bushings? It def happens when the weight is off the front tries, like going over a dip in the road.

 

Pazee, finally the problem was a leak in the Megan headers. When bump the leak "open" and the sound and vibration increase drastically.

At least the headers broke.

 

Glad you got it sorted out. Thanks for updating the thread, most people don't.