I have an 2004 DG MT G35 coupe and about a month ago, my car started to get the shakes or idle kind of low.......the idle is not too bad......you notice the idle when the car is sitting still...... So I finally got around to take it to the dealership to let them have a look....... They noticed the idle and hooked up the ECU to check things out..... Well they told me that everything was within operational specs and that they could not do anything about it....... I talked to the service manager and asked if it might be a bad spark plug, clog fuel injectors, or maybe the timing was off, etc.....well he told me that there are so many sensors on the car that it would throw a check engine light......so that was that..... the other day, I decided to run the car pretty hard...... and noticed that the car does not pull as hard as it did......even at around 4000 rpm........ its like the car is lossing horsepower and torque...... I figured I would post on the forum to see what some of you guys think what the problem might be........ so that I can tell the dealership......

Oh, I forgot to mention that when the dealership looked at my car, they supposedly fix the problem with the gas tank shutter valve......but the past two times I filled up my tank, the problem filling up still happens.....so I'm thinking that the dealership really did not look at my problems with the idle and gas tank valve...... I want to fill a complaint with Infinit, but was wanting to know what you guys thought first......

 

You can have the dealer to reset your computer for you, once I felt loosing power and torq on my car after the exhuast system I purchased. But when I took it to the dealer and have them to reset the computer for me. Wow, power is back and feels even stronger between 3500 to 4500 rpm. Hope it will works for you.

 

you might want to start your engine and pop the hood. Put your ear near different areas of you engine bay and listen for leaks. You should do this with someone else press the gas pedal slightly. Whooshing or hissing sounds, Especially around the manifold area. Most of the time idle problems and acceleration problem stem form some form of gasket leak around the manifold or headers.

Sometimes they are hard to detect. Do a google on detecting manifold leaks to see if you are experiencing any of the symptoms.