Not long ago I had my alarm put in. The next day I was driving my check engine ligth came on. I suspected the installers did something to, but when I went to my mechanic he said that has nothing to do with it and it's only coinsidance. He tested the car on the computer and said that one side of the engine is not getting enough fuel. He said that, this is caused by the MAF sensor being bad. Also when that happened, I noticed that when I wait at the red light etc, my rpm's fall down to 500-400 and go right back to 600 (which was normal before the check engine ligth). Could it be really MAF sensor or something else???
if yes, how much do they cost?

 

what year is your car and can you go above 2400rpms. and they are $$$

 

Looks like you gotta get it fixed....no other options. I put an intake on my car & the next day the check engine light came on. I took it to Nissan & they were gonna charge me $35. So anyway all I needed to do was reset my computer. The light went off like 3 weeks later so no more worries. But sounds like you have larger issues than I did. Good luck.

 

Go to www.car-parts.com, I found a used MAF for 35 bux. They usually go for ~400-500 dollars new
Try resetting you ECU, directions are on a stickie on top the 4th gen forum page. If it goes on again, you got a problem.

 

go over 2400 rpms. and actually after driving for couple of days now the rpms do not fall down anymore. Just the check engine light is still on. It went away once for 2 days but It came back...