Hello,

I have a 2006 Nissan Maxima and for the past few weeks I've noticed my car has a slight fuel smell. I's not very strong and doesn't smell all the time. There are no visible leaks and I don't smell it when I lift the hood it's more in the rear. Any suggestions what this could be? I've replaced air filters and made sure my gas cap was tight.

 

Not for anything, I've heard gas caps, like a radiator cap, sometimes needs to be replaced. That said, it could still be just about anything at this point. I'd be very cautious, could be a catastrophic ending one day. If you have the chance to get someone to drive it and follow close behind in another ride. If you smell fuel wafting behind it while it's driving, you've got a serious problem. To note, most fuel leaks aren't easy to find because of how fast gas evaporates...

 

If it smells more when it's cold outside, than it very well may be one of the rubber fuel hoses leaking from under the clamp. Had this issue with my 3d gen Maxima, the short hose connecting front and rear fuel rails under the intake started leaking just enough for gas smell to get into the vents.

 

Hope this helps, last year my 07 developed a smell as well discovered it was the fuel rail at the pressure regulator. you really smelled when engine was cold and could se it dripping done with the engine cover removed, but once it heated up it expanded enough to stop leaking. I bought a new one from John Lee Nissan in FLA for a decent price around a $100 and that fixed it. My mechanic said you can try to fix it with new gasket but for the price he said better to replace. he even thought the engine responded better after replacing. good luck