2008 Pathfinder/Code P0455

[brc19761]

Yesterday the service engine soon light came on for the first time. It stayed on all day. When I got home I hooked up my ob2 scanner up and code P0455 came up. I was researching the code. People state it is a very common code on Nissan models, especially Pathfinders. Said it could be from a faulty gas cap all the way to a leaky vent valve.

Is there any steps I can take to narrow down the problem?

Thanks,

brc

[atraudes]

Before doing anything, make sure the gas cap is secure, clear the code and see if it comes back.

Next visually go over all of the EVAP components, and see if you can find any cracks, cuts, or disconnected vacuum lines.

If that doesn't bear fruit, get a new gas cap. If you do, get OEM (though I used Gates and had no problem).

P0455 basically means there's an egregious leak somewhere in the EVAP system. The common culprits that I've seen around here are gas caps and charcoal getting lodged in the vent control valve. However, since you aren't getting any accompanying codes (and your 08 vehicle shouldn't be old enough for the charcoal to disintegrate yet), I'd focus on the gas cap and filler neck first.

Do you hear air being sucked in when you pull the gas cap and the fuel level is lower? Do you smell gas anywhere? Gas odors would be a really strong indication of where to look.

Some links that may help if you haven't read through them already:

post6554628.html
post5493422.html
http://www.nicoclub.com/FSM/Pathfinder/ ... der/ec.pdf

Let us know what you find!

[brc19761]

Hi, thanks for the response. I did erase the code with ob2 tool. I drove it all around town the next day and the light stayed off. That night when I started it up to park it in the garage the service engine light came back on. With the holidays I haven't had time to do much of anything. I did clean the gasket in the gas cap. But I have not had time to reset the code and drive it. I need to get underneath and under the hood and check for leaks and gas smells.

There is one thing that did come to mind. Ever since I have owned the pathfinder when you put gas in it takes forever for the gas gage to register the correct amount of gas. Like there is something wrong with the float. It also takes a long time for the screen above the radio to recalculate the gas millage. Would that set off the code?

[atraudes]

I'd say keep the gas level gauge issue in mind while you're working through this, but I doubt it's related to the P0455 code.

[brc19761]

Thanks for the reply. I will be working on it today.

[brc19761]

I bought a new gas cap from Autozone. It wasn't a cap off the shelf it was one made specifically for the vehicle. I drove it around all day this past Thursday with the new gas cap and the service engine light did not come one. I drove it about seven miles up the road Sat. and the service engine soon light came on again. I came back home hooked up the scanner and the same code P0455 came back.

Do I need to buy a gas cap from my local Nissan dealer? What other things can I check, such as specific lines in the engine bay and underneath the truck? Any input would be greatly appreciated.

Thanks,

brc

[atraudes]

The gas cap could still be problematic just based on the stories I've read, but your guess is as good as mine.

Unfortunately I'm not personally familiar with the physical EVAP system, but this link may give you an idea of what you're looking for. I think part of it's located underneath in the back around the spare tire on mine.

[brc19761]

Thanks for the response, the info, and the link. I hope there is a simple solution to this fix.

brc