I have about 2,200 miles on my '07 G35x and this is the second time the SES light has come on in the last 1.5 weeks. The first was my stupidity (didn't have the gas cap on tight enough). After about driving 100 miles the SES light went off. But this time, I'm a little perplexed. I'm in the Baltimore area and we are having pretty weird weather right now. One day it's pretty cold and the next it's pretty warm. Yesterday, we had a fog. I was driving and went to set the cruise control and that's when the SES light came on. I'm wondering if the rapid atmospheric changes could be causing the SES light to come on. There are no signs of anything else wrong. No decrease in power; no weird noises; nothing seems to be wrong.

If anyone has any ideas, I'd love to hear them!

 

I had the same problem with my 07 X. I had a SES light come on early in the break in period. I traced it to the gas cap like you did. I have not had it come on since. If it came on again and the caps not to blame i would bring it in. You said your light took 100 miles to go off after the cap incident? That seems like alot, mine took like 15. Were having up and down weather here as well. I live in Rochester, NY. Ive driven through fog several times and hot and cold weather with no problems. I wouldnt use the laser cruise in the fog. Might interfere with the sensor. Id have it looked at if the lights not going out... If it starts to blink, Proceed to the dealer QUICK.