Ok well I purchased a 2004 G35 coupe auto today and drove it about 300 miles. Near the end of the drive the check engine light, VDC off, and the Slip lights all came on as the car studdered for a brief sec and then seemed to drive fine. I pulled over a few miles later and killed the car to see if the lights would stop. Then when I went to start the car it took about 3-5 seconds to start while turning over. After she started I was able to drive her home with no issues in drivability. Once I got home I again killed her and tried starting her and once again she took awhile to start but she did start. I then went through the steps to read the trouble code in the computer using the CEL function. The code I got was 4003? I've looked all over to see what that code means but can't find any referances to its meaning. I'm positive that's the code it gave and I watched it read the same code over and over it was the only one it displayed. I then reset the CEL and cleared the codes. After resetting the codes I went to start the car and she started right up no hesitation?!? What could be my problem? I plan to drive her to work tomorrow so I will see if any codes pop again but if anyone has any insight on this issue I would really appreciate the help... Thanks in advance!

 

I had the same problem about 6 months ago. I dont remember very well the name but i think it is the camshaft sensors there are two do some research to see if thats the real name. All i know is, there are two sensors that help the engine to turn on. It looks like this