Hi All,
Recently purchased a vehicle i have been drooling over for quite some time, 2004 G35x sedan. It is in really good condition , but had it checked out and came up with code 0455, large leak in EVAP system. I've read around and it seems like a gas smell is supposed to come with this problem. I do not smell any gas. I checked the gas cap and it seems to be sealing fine. I would think if it was a crack in a vac line or something like that it would have given a 0456, small leak code. There are also other codes for solenoid and valve problems, so why just the large leak. Hopefully someone can give some advise here as i dont want to go full on diagnostic and test each componenent. Could it be as easy as disconnecting my neg cable and letting it sit for 30min., reconnecting and letting it run through its drive cycles? Thanks for the feedback , I'm looking forward to learning alot!

 

Let me clarify a little. I'm looking for common issues or known problems. I Have the service manaual and know how to diagnose, thought i would ask to save some trouble and time on my part. I have searched the topic, but have only seen the same vague answers listing the same laundry list of possible causes. Thanks!

 

Welcome to g35driver, you fellow '04 sedan owner You can disconnect the battery and step on your brake to let out any residual electricity so that your SES light resets, then re-connect it and drive around and see how it goes... if the SES comes back on, you either have a leak or a bad sensor... If you have a leak, I might recommend taking it to a professional because EVAP leaks can be hard to find... unless you WANT to spend a lot of time troubleshooting rather than enjoying the G

I'm in the same boat right now actually, P0442 small evap leak... gonna take mine to a dealership in a few weeks and get it diagnosed, then take it to a g35drvier member that's done work for others and have him fix it for cheap

where are you from??

 

Thanks for the tip RAD. I was going to disconnect ground last night, but the 12-24 hr. wait that i've read about, didnt fit into my plans. Thats a nice trick with the brake peddle! I ended up ordering a new evap canister control valve from ebay for $46. From my searches, that seemed to be the primary culprit in most cases where there was no gas smell present. If that doesnt do it, I can resell at discount.
Sorry i haven't filled out my acount info yet. I'm from PA. I usually do all work possible on my own vehicles. That list of things has shortened over the years though. Lol. I actually owned a 1984 300z, first car I financed, and am surprised that this engine is very similar, with the exception of electronics and fuel induction. I just purchased my G a couple weeks ago with a decent warranty and plan on taking it to the local nissan dealer soon to go over the vehicle and make sure everythings tiptop. Got lucky, cars pretty mint stock.

 

The brake pedal trick worked like a charm, no code( crossing my fingers) and engine light. Hoping it stays out. I now understand why pop chargers are so popular. That stock filter is a **** to change. I'm actually considering gluing the air box together, taking a dremel to it to cut out, and putting a pop filter on. I'm sure thats been done before.

 

Did the Evap Canister Control valve fix it for you? I've had the same issue for awhile...

 

I doubt the original poster is active in the forum

Fuel issues have not been a common problem in this car so you won't find a ton of info, most likely.

If it is a "large leak" you should be smelling gas while the vehicle is on...from somewhere. It would even be likely to possibly see a leak.

 

if you had a code from the evap valve and a code for evap leak.
with the power of puzzle piecing, the valve is faulty there ford evap valve code and since the valve is faulty it won't hold evap pressure during testing thus the evap leak code.
hehe