Anyone else experiencing this slight vibration at idle? Almost feels like the exhausts are clogging up and clearing its throat every few seconds.

 

The slight vibration you're talking about could be a rough idle. If the exhaust is 'coughing' as a result it would indicate a problem.
The exhaust on my Coupe coughs a little which I consider normal, and also the engine idle is such that the motor does not rock at all and is smooth.
After a warmup, check the smoothess of idle, and if the car seems to be driving ok then the symptom you're describing is prolly normal exhaust noise.
If there are other symtoms, such as poor throttle response and power, or abnormal gas mileage, then you'd better get the shop to check it out. With their 'Consult II' scan tool, they will know if there is a faulty sensor, or bad adjustment. G/L

<font color=red>GSM</font color=red> <font color=black>Silverstone Coupe</font color=black>

 

what would be "bad" gas mileage ???

info in the nav shows I'm averaging 12 to 13

Mind you every shift is over 3500 rpms .... and i like to flat er out fairly often ...

not unusually though ... sooo????

wussup???

later man

 

also sorry to jack the post ther

whats you mileage and whens the last time you did a oilchange??

later

 

12-13, ouch! You gotta stop cruising around at 6 grand.

 

Hey DC, I think most G's (at least coupes) are 'bad' for gas mileage --- a result of high performance engines and perhaps too aggressive timing and fuel mapping settings in the ECU. Check out Chebosto's thread in Tech forum for some good reading on this.
What I meant b4 was that if there's any 'deviation' to your normal gas mileage, it will indicate that there's a problem all things being equal.(same driving style, fun factor etc).
To my mind, a good indicator for mileage is to travel as long a distance as possible, with cruise control on, on a freeway to get some idea of what your engine is capable of. That would be your standard mileage to compare to next time you check mileage.
I know that mine on the 401 at 100-110 kph with cruise on will yield about 32.5 mpg's without A/C on, and about 31mpg's with it on.
If it suddenly only gets 25-26 mpg's in the same driving conditions, then it shows there's a problem.
If this happened, I would think that the idle would be different, and or rough, and driveability/power would be changed too.
You said you're "averaging 12 or 13" with your style of driving--- do you mean mpg's or is that the indicated liters/100 km?
12 or 13 liters/100 kilometers converts to about 23 mpg's (imperial).....not bad (for this car) with some aggressive driving.
If that's 12 - 13 mpg's then you're "flatting out" more often and sacrificing mpg's for fun.
Gas mileage on these babies isn't a strong point, lol . You'll know if it's not running right and you're having to gas up more often. Just have fun.
laters

<font color=red>GSM</font color=red> <font color=black>Silverstone Coupe</font color=black>

 

Hey Diamond G, I have noticed a very light "coughing" at idle when warm...around 650 RPM. it's a very light "Put", "Put"...sound, hardly noticable unless your really listening for it. It could most likely be the variable flow muffler we have with diverter baffles...I just think at idle, the exhaust pressure builds up and opens the baffles a tad to relieve the pressure..that's what I believe we're hearing. It's not the engine..it's smooth as silk.

Growler

 

i have a similar problem, its doesnt happen all the time. It sounds like its about to stall or something.its hard to hear but if u open the door and stick ur head underneath u can hear it. if u gas it slightly it goes away.
I also notice a similar unhealthy sound SOMETIMES when turning off the car. hmmmmmmmm?

03 G35 coupe SS (GD) 6spd everything but navi
02 QX4 pearl white
00 528 Silver on black

 

I previously had an occasional rough idle. But I've had no roughness in the engine at any RPM's since about 1500 miles when I installed a HyperGround kit on the engine. I one I bought and the grounding points I used are at http://www.z-xtreme.com

Dr. Jim
2003 Desert Platinum G35C 6MT/Aero/Prem/Nav/HyperGround/XMSat/BSM/Tint/ClearBra/CG
2001 Acura MDX/Touring/Nav
1997 Mercedes Benx E320/Eibach Springs+Dampers/OZ Racing Superleggera Wheels

 

I have a question for you guys...i have been hearing a noise that fluctuates with the engine...i can only hear it when i am inside the car though...outside, all you can hear is the exhaust (stock). The sound is what can only be described as a helicopter that is far away...it sort of sounds like a vacuum or air movement with the engine RPM's. Could you guys give me any insight? Thanks.