lexgolf

I have had raw fuel smell in my 2012 LS460 (left passenger side) when I come home after a ride out in the AZ heat. The garage smells pretty bad. It happens when the fuel tank is nearly full. Took the car to local Lexus dealer. The SA says that it is just the fuel expanding due to the heat, and there is no place to go so the system purges it. They have had several (3 I think) LS460s come in with the same complaint.
I sent the car back saying you must do something to diagnose the problem. They elevated the problem to Lexus factory technical support, who told them to pressure test the fuel system. No trouble found. The charcoal container seemed OK.
My question is: Has anyone else experienced the same issue?
Many thanks for replies.

comotiger

That doesn't sound pleasant. It also could be a health or fire hazard. It seems like Lexus knows exactly what is going on (purging to reduce pressure in fuel tank), and that the system is working exactly as designed. I am guessing the smell is worse on the left side maybe because some vapors are venting thru the gas cap. Has this been an issue with your other vehicles? You may have to figure out a way to ventilate your garage.

jmcraney

You probably already know, but in case you don't: The cars are equipped with a vapor recovery system that is mandated by the EPA and no vapors should be leaving the car. If there is raw fuel leaking then that is another problem. As to the vapor recovery system, the fuel cap is a very important part of that system. You must tighten the fuel cap, every time you close it after refueling, until it clicks once. That click that you hear is an indication that the fuel cap is adequately torqued to prevent escaping vapors. And, of course you should not try to top the tank after fuel nozzle auto-shutoff when refueling because if the fuel is very cool and the weather is very hot there might not be enough space for expansion.

CJITTY

I posted about this a couple years ago..you can search on the topic. I was due for the fuel pressure recall and that took care of my issue once fixed

roadfrog

CJITTY took the words out of my mouth. There's a recall on this. I occasionally get that same smell, and I haven't ad my recall done yet,

Nospinzone

There was a fuel rail recall for the 2007 model, was there one for the 2012 as well?

I'll bet that the problem is topping off the tank in blisteringly hot weather. I saw 111 degrees in Phoenix the other day.

jmcraney

The fuel pressure sensor gasket recall was for LS460s in the 2007-2010 model years.

No recalls on the 2012 LS460.

AandSC

I had a similar problem on my LS400. Replaced the fuel cap and no more issues.

lexgolf

I replaced the fuel cap. The Lexus service center did a pressure test on the fuel system and no leaks were found. I asked about the cost of replacing the charcoal container in the vapor recovery system and was quoted $1,200. I decided to not do it for the time.
If the problem still persists, I am selling this car and saying goodbye to Lexus. That would be the second brand I have sworn off. The first was BMW.

DrQuality

I agree with the other posters here who are attributing the charcoal canister in the EVAP system ... since the OP stated it happens when he tops-off the tank. If you top off the tank, especially in hot weather, especially if you pump more gasoline in after the pump handle cuts off, the gasoline will expand as it warms-up and spill over into the canister, soaking it and causing it to emit gasoline fumes until it dries out. If you do this often enough, it will damage the canister and will need the expensive replacement.

This is not specific to Lexus. I previously owned a 2006 Toyota Avalon and it did the same thing several times ... only when I topped it off in very hot weather ... and others have told me it has happened with other various brands as well. As a result, my habit is to never fill to more than 3/4 (unless I have a special reason for needing to do so). When I am pumping I am looking at "gallons in" (rather than the price) to estimate when I reach 3/4.

I also run no LESS than 1/4. That's because if you run the tank empty you are overworking the fuel pump (that requires good flow of gasoline for lubrication) and that can wear it out, also often an expensive repair. Also if you have any water or rust or jellified gasoline or whatever resting in the bottom of the tank, if you run close to empty that junk can be pulled up by the fuel pump and foul your fuel system.

And, yes, the smell of gasoline fumes can also sometimes be attributed to end-of-life of your gas cap. The seal doesn't last forever. If so, it will often also trigger your check engine light as an o2 sensor is picking up on the air leaching into the fuel tank. I drove the Avalon out 15 years to about 150k and I had to replace the gas cap twice.

A third 'usual suspect' is that the vehicle is running rich. A common cause for that is a dirty or failed MAF sensor that is mis-detecting the amount of incoming air and so mis-adjusting the air/fuel mixture. You can usually fix a dirty MAF sensor by removing it and spraying it down correctly with about 10 quick squirts from an aerosol can of MAF sensor cleaner that you can pick up at the auto parts store for about $10 then letting it dry out completely before you reinstall it.