Hi everyone from cold Boston.
I have a 2005 G35X sedan with 105K miles on it.
I have the car in the shop today (not dealership but a trusted shop) for a few items which I'm hoping you can help me diagnose because they are not finding anything significant. No check engine lights are on and car is not running rough. Here is what I have:

1) Car has the strong odor of fuel on initial start up then when it warms up smell goes away.
2) Faint smell of oil (or other similar smelling fluid burning) is coming through vents. It's not strong but faint. Mechanics don't see any signs of any leaks anywhere.I am not going through more oil than usual.

Mechanics said no leaks are visually present on anything. Only thing they found is both the cabin filter and air filter are filthy so they are replacing those. I asked if perhaps a tune up is needed but the car runs fine. I don't want to spend any unnecesary money if these items are not needed. They didn't think it was warranted.

Any ideas on those two smells above? Anything I might ask the mechanic to look further at before I pick car up at the end of the day?

Thank you,
Mary

 

Have someone stand behind the car and see if the fuel smell is present in the exhaust. Could be running rich on cold startup.

Normally, cars do run rich at that time, but it's hard to judge over the net if that is a normal level of fuel smell, or excessive

 

Oil smell could be leaky valve covers

 

The oil smell seems to be gone now that the cabin filter is new. Maybe it was just normal engine compartment smell getting into the car because the cabin filter had a chewed hole from a rodent. I am going to fill my tank with high octane gas and see if that helps the gas smell on cold startup. I use 87 and it runs fine but maybe better gas will help the emissions. Thanks, all.

 

The air intake for cabin air rests in that black plastic you see behind the hood. It is a small intake box very similar to your engines intake . I wiped mine down and that helped clear up the smell a little bit.