G37X GraSdadow

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I noticed that my car vibrates irregularly when I'm stopped at traffic light.

I know that it is not because of engine mount because on neutral or park, the car is very quite with no vibration.

I can only feel this when my car is on driver mode + brakes are applied at full stop.

Rotors and brakes are pretty much brand new, alignment and balancing are good too.

My guess is it might be low on transmission fluid? the mileage of my car is about 70k miles.

Infiniti 'could not' duplicate the problem..which is so stupid

.. Any suggestion?

GoadG37Q45

iTrader: (1)

Do you notice a slight RPM drop when the vibration occurs? If so, My guess would be dirty throttle bodies. Easy fix, take apart/clean them. I had a stumble similar to yours and that's what I did. Also found out I was not up to date on the latest ECU update. Might be something to look into.

qmantran

That doesn't mean you can rule out motor mounts. Sometimes bad mounts will seem smooth in park or neutral and show vibration while in drive or reverse.

A slight misfire can also cause irregular vibration and still not trigger a check engine light

G37X GraSdadow

iTrader: (1)

No Check engine light
Latest ECU update
constant RPM while idle/stop - 1.5k Edited: not 1.5.. 0.7k.

Not sure if I want to drive 40 min to go to infiniti to service it again..

Nissan dealer is 5 min away from me. But I don't want to pay for diagnosis fee
(I have Infiniti elite extended warranty)

GoadG37Q45

iTrader: (1)

Your idle is a constant 1.5k ? While stopped? You def have an issue there. I would get it checked out. Your roughly 1k RPM over what you should be .

TBau651

Your definitely idling to high. Any loss in power while driving? shifting issues?- As GoadG37Q45 mentioned above, probably wouldn't hurt to get in there and give the throttle bodies and MAFS a good cleaning (mine were filthy at about 45-50K). If you have intake mods maybe check for any loose or cracked couplers, leaks, holes, etc. From there I think faulty MAFS, Plugs, Injectors???

08STLX

1.5k dangggggggg....mine is about 2k on a cold start up then 600 at a stop light after that.

I just cleaned my throttle bodies (didn't do the MAF) and noticed a little improvement in response but my car is still a bit shaky at times. Nothing huge at all but something a car guy like us would notice. Last night I threw in some Gumont and I think in a month or two I will do the plugs.

SkyG37

Check your driveshaft. Could be ripped. If you go under my threads and look at the Ark review one, I write about how I noticed a ripped piece connected to my driveshaft while installing my exhaust. This caused rough vibration during stopped and caused weird rpm problems.

Took it to Infiniti and they said it was the problem. They ordered a new drive shaft and installed it under my powertrain warranty. Now I domt get any vibration unless it's drone from my exhaust

AUR11

I have this same issue and it is driving me crazy. I can't hear it outside of the car, just inside.

lokrain

iTrader: (1)

I have the same situation on my coupe but my rpm is at ~600-650 when in D. Members here suggest to clean the throttle bodies. I did and it helped a little bit. I took my car to the dealership and the service manager said I needed a fuel injector cleaning/service and asked for $150. I'm not sure if cleaning fuel injector would help cause I haven't done it yet. If anyone can comment or give advise on the fuel injector, please go ahead and greatly appreciated.

G37X GraSdadow

iTrader: (1)

nvm its 0.7k rpm lol..

GoadG37Q45

iTrader: (1)

I'd reset your ecu. You can do it without disconnecting the battery. There is a guide on you tube. Try that and see if it persists. I wouldn't rule out the TB's though.