Fuel smell in the garage. Seems to be originating from the gas cap area, so I tried a new cap and no success. I did not notice any fluid/gasoline leaking, just the smell.

Anyone have experience with vapor leaks in this area?

 

Not saying that you have this particular issue, but 04s are known to have the propensity:
https://www.corvetteforum.com/forums...read-this.html

 

Could be the EVAP vent solenoid starting to go [or stuck open]. Its on the right rear side by the tranny. It basically allows air in and out of the EVAP canister so when stuck open...you can get the fuel smell. If you have a scanner that's bi-directional...you can test the evap system to see if its functioning correctly. Did you fill the car up recently?

 

with the fill up comment. Even though my VIN does not fall within the possible cross over fuel pipe issue, several years ago I got a fuel odor smell in my '04 Vert. after filling up. It went away after the driving about 50 miles. Now, I no longer 'top the gas tank off' and have had no further fuel odor smells.

 

Filled it up about a week or so ago. Probably at 3/4 now when the smell began.

 

I took it to a shop today and they could find no evidence of a fuel leak. They suggested I try parking it outside for a few days!

So when I got it home I hosed the whole gas cap area, dried it off and parked it in the garage. I walk out there a couple hours later…and the garage smells like gas!

Damn…

 

Damn, that kinda sucks all right. Any puddles, or new stains under the car? As a guy that once had a gas fire in his garage, I'm concerned for you, my friend. This could have tragic consequences, just sayin'. I'm sure you realize that. No codes? Obviously, it has to be in the venting/evap system, or pressurized side of the system. Maybe a leaking fuel filter?......

 

I appreciate what you’re saying about fire, so it’s back in the driveway for tonight.

No traces of a leak on the floor, and it’s my understanding that the ‘04 fuel filter is inside the fuel tank. I park over a sheet of plywood so any stains will alert me to a leak somewhere. Zip. No codes either. I bought a generic gas cap, and since that hadn’t worked I ordered an ACDelco cap, like a Hail Mary.

Going to look for a shop that can at least do a smoke test to find the source.

 

Maybe the wife playing tricks on you to try and get you to sell it by sneaking down at night and spilling a little bit of gas

On a serious note, minor fuel leaks are hard to find because...gas is highly evaporative. Exxon valdez size spills easy...faint ones...hard. In the older carb'ed days...I'd pressurize the hard line and wait to see a dribble or smell fumes and then trace from there. Another idea if its really bother you would be to mimic the same thing in a FI scenario. Jumper the fuel pump and let it run [pressurizing the system] and see what you can see and smell. Honestly...absent any puddles...it sounds like a venting issue to me which...granted the system is supposed to be closed loop but...absent the smelly garage...is not real threat or danger [past Ozone effects lol]. Keep driving her and shaking it down. Maybe the filler neck hose has an abrasion? Could be something like that.

Joe

 

I like this idea. With no visible leak trails it seems vapor is the most likely culprit. I suspect the shop needs both a fuel safe generator and a lift so they can monitor the cross over tube.

I recall a thread at some point where a fastener had been installed along floor ridge where the cross over resides, and had punctured said hose.

 

Following this thread. I have a 03 with early style system with external filter/regulator and pump at the bottom of DS tank.

I noticed when I fill up and then autocross I can see a small fuel leak on the PS tank somewhere from the top that drips down the tunnel. If I only fill to 3/4 tank and autocross, no issues.

 

Filled it maybe two weeks ago, at about 3/4 now. I don’t even know what a bi-directional scanner is 😁.

 

Just now I go out to move the car so my wife can get her car out…..and no gas odor!

WTF ? I sniffed all around the gas cap and zero odor. In fact it smelled like good old plastic. Now, it was parked with that side getting baked by the sun. Anyway I parked it back in the garage to see if the odor returns. There’s something really strange going on around here.

 

Uh…that’s a hard no. Fumes are back. Got all day open tomorrow to either find some help and/or jack her up and start looking around.

 

BREAKING NEWS !

No leak with less than 1/2 tank. Must be the dreaded plastic elbow on top of the fuel pump.

I read up on this little bastard, and attached a video of the usual problem. Unfortunately, GM decided to switch from a flexible rubber hose to a metal fuel tank crossover line on the ‘04, requiring removal of the drivetrain to drop the driver side tank/fuel pump. Just peachy.

My preferred shop has a 6 week waiting list, but at least I can garage it now that’s its not leaking and creating gas fumes.

 

I knew it was filled to the hilt Yeahhhhhh...just throw a 20 in her from when you get low and cruise on that. Luckily for me, I have so many in the fleet...seeing "F" is a rarity as I'd need a 2nd mortgage to fill em all up

You dont have to remove the rear section or cradle...but it does make things 2000 times more accessible if you plan on dropping BOTH tanks (which if going through the effort of drive train removal...I would undoubtedly do if paying someone labor). A forewarning though in my research for the job as I have to do it myself at some point...new crossover tube (as the old one will break upon removal), if you can afford it...just buy a basket with the pump already installed and wired up (racetronix unit looks tempting), If its a manual car...now would be an opportune time to inspect clutch, rear main, and TT...especially if the rear drivetrain is coming out.

Joe

 

I was wondering if I should get a notch better pump, “while I’m in there”. I do plan on a midrange cam and upgrading to 243 heads, but no idea if that would warrant larger injectors needing a better pump.

Now if I can get the driver side tank out without pulling the driveline, that would be just dandy 😎…but this ‘04 is fitted with the hardline crossover. I have no experience with this, so don’t know how that particular crossover plays. I’ve had the drivetrain out twice in two years, including new clutch, and rear gear change. Was kinda looking forward to more fun parts, so this gas thing is a buzz kill.

 

This is coming from a 04 perspective as I also have an 04 lol My fuel pump and crossover tube appear to be fine but my blasted gauge dosnt work, and cant get any more then 6 gallons in the car so something is going on. When I do tackle this job...I'm replacing EVERY GOT DAMM THING I CAN in reach lol During my wrench for pay days I called these kind of jobs black holes...and put it to customers as such. Most times they agreed, but in a few cases, something else failed down the road and guess what...10 hours of labor to get to it again. Please reference your invoice from X date where I recommended this part be replaced during Y job...and your signature declining lol I tend to not replace good working parts when they don't need to be. But boy oh boy...if a driveline has to come mostly apart...you bet your *** I'm machine gunning new parts in where ever I can lol For my pay-for-Labor guys, this does one primary thing for you...insulates you against having to pay repeat labor if something goes awry as in the scenario above [shops hate this]. Sometimes their recommendations are unnecessary. But many times, they don't want comebacks so their recommendations are sound in that they know you will be back and bitching lol No way I'd recommend at 20 year old crossover tube going back in when I knew I had to sumo wrestle that **** out and trusting that brittle *** plastic ring on the inside to hold. Nope!!! In a for-pay situation if a customer delcined a new crossover tube or checking the passenger tank while we were there...I'd ship the job down the road because WHEN it goes back together...and WHEN the customer states his fuel gauge dosnt work...It's coming back to ME and the customer aint gonna be pleased...despite me telling him so prior to me taking it apart. Money's tight for everyone...but an ounce of prevention is worth a pound of the cure.

Joe

 

One video also suggested replacing the pump wire harness. The particular one he displayed look old and crunchy, and the weather seal was toast.

Interesting feature on the Bosch pump vs the GM, is Bosch added a plastic gusset to the wiring connection on top of the pump. The electrical junction is a known location to crack and leak, yet GM still cranks out the old design.

 

At fuel station this afternoon, filling-up my '04....all was good until I noticed a stream of fuel coming from under my car!!
Before I purchased this '04 in April the dealer had the fuel pump replaced....this was the first time I attempted to completely fill the '04.....ended-up driving around until I got the fuel level low enough so that no fuel came out.
Have not got under the Corvette yet, suspect I will find either the crossover tube broken or loose.
So in preparation for this...what are the part numbers I am going to be needing should I have to replace the crossover tube?
And it is correct that the drivetrain has to come out??....please tell me no.....