NTB04-028 "Air / Fuel Sensor Heater / Closed Loop (5sp AT Only)"

Have any of you had this done to your '04? If so, can you tell me the symptoms that caused the mechanic to do this?

I have a problem with my '04 where when it is started on cold mornings, there is a strong gas smell in the car. This smell goes away once the car is warm (usually 10-15 minutes). The Nissan dealer can't find anything wrong, "We didn't smell nothing." But the day they had it, it was hot and they didn't even begin to look at the car till afternoon.

I bought the car 3 weeks ago and other than this gas smell in the morning, I love the car and I can't wait to start some "improvements" that I've found out about thru this site!

 

you should give the car a chance to break in, maybe after a few thousand miles the smell will just cease to exist.

 

I've already put 2500 miles on it since I got it (26000-29500). Like I said, the gas smell is strong when first started and once warmed up, it goes away.

 

DTinVA - I'm not positive what could be causing this, but noticed you have not yet had a solution to your problem, so will give it a try.

Are your windows closed tight before you start the car? Are you positive you have not walked where gasoline may have been spilled and dried, leaving a residue on the ground which your shoes pick up?

Since the smell fades as you travel, my suspicion is that there is a tiny leak of gas somewhere in your engine compartment. Even the tiniest amount would put the smell of gas in the air under or in the engine compartment, where it could be picked up by the H/AC system when you are starting out IF you had the controls set to bring in outside air.

As the car moves along, most of the air brought in is now fresh air from in front of the car, and the gas smell fades away.

I am not familiar with the TSB you referenced, and it may be intended to address this problem. All I can say is that there is no place where the fuel system in your Maxima should route even one drop of gas into the passenger cabin. The only way the smell could be coming in is through the H/AC ventilation system, which is picking up the smell from either a fuel processing problem or a tiny leak in the engine compartment.

Try things like closing off the outside air in the H/AC system before you park the car, and be sure to keep the H/AC system closed to outside air when you start up again.

If the smell is much weaker or gone, then you know there is some way a tiny bit of gas is managing to get out of the supposedly 'closed' fuel system in your car, and the fumes are being brought into the passenger cabin via the H/AC system. I would not think the TSB would fix this.

If, however, the smell of fuel is as bad as usual, then the smell is not in the air in the engine compartment, but is somehow being added to the air by the car's fuel and H/AC system, and might be the problem the TSB is intended to fix.

Good luck in getting this fixed. And you DO want this problem fixed. There is no market for toasted, scorched or seared DTinVAs.