Fuel odor when filled up

Not sure what the exact dividing line is, but when the fuel level is, let's say, less than half full I do not detect a gas odor. But when I fill up the tank, wow, the odor hits me like a brick.

I suspect there may be a leak near the top of the gas tank but who knows?

Wondering if anyone has experienced the same issue.

 

Welcome to the club.

I believe it to be the gasket near the top of the tank for the fuel lines and pump that dries out but I’ve been unable to confirm.

 

Question: Are you getting any codes? And before you say, "There's no check engine light on!", those burn out. Scan anyway.

Just curious if you're popping any EVAP codes. That said, any codes you may have stored or pending could point to other issues. If a gasket is blown or the tank isn't sealed b/c, say, a crackhead drilled your tank up top, I'd expect at least a small leak code.

 

The odor has been present for a while (until the fuel level decreases), before a code popped on the dash.....which occurred today. Not much detail...P0440 Evaporative Emission System

 

I have the same thing occur ever since I bought my 04 back in 2021. Very strong odor every time I'm filling up. No CEL, no EVAP codes. My truck fills up "slow," as in I always set the fuel pump to slow filling otherwise it'll auto-stop I'm sure it's related. Jack and shifty are probably correct in what the problem is

 

P0440 could be the charcoal canister. P0441 is usually the gas cap code.

 

P0440 is a large leak. That would jibe with what you're experiencing, i.e. heavy odor when the tank is full. I doubt it's the gas cap, that tyically throws 'small leak' codes (P0442) on most cars.

Flipping thru the 2nd reply in the megathread, it doesn't look like the '02 was susceptible to the faulty fuel filler neck. I guess the advice I'd give you is this: Fill your tank up to brimming full. Drive it back home, get out a powerfull flashlight and look all around the tank for clear signs fuel is leaking out. Look for any unexpected holes, cracks, fluid dripping, both on the tank and the EVAP/charcoal canister near/above the tank like BMF said (I think it's on top of the tank in your year, or next to it?). If you can see on top of the tank with a mirror, check for signs of chewing. From that thread, the type of chewing I'm talking about:

• RODENTS: Lots of plastics, wire sheaths, etc. in these trucks use soy-based plastics. If you have rodents nearby, or you park outdoors regularly, it's not uncommon for them to crawl in the opening under the intake manifold, where the starter & knock sensors live, and chew up the wiring (no start, knock sensor circuit codes). Likewise, they love nesting on top of the gas tank, and they'll chew up both the wiring like this, killing the pump (no start), and chewing up the tank tubes/plastics like this (EVAP codes, EVAP small leak, EVAP large leak). They'll chew through the gas filler neck, which will also throw EVAP codes, like this. It's common enough we can share exact photos of it, and there are more where those came from.

 

I have been getting the "small leak" code (can't remember the number) and a faint fuel smell. The dealer performed a smoke test and diagnosed the gasket at the top of the fuel tank. That fixed the problem (so far). Losts of $$$ in labor, not much in parts, but if you want an inspection in NY state you have to fix the CEL.

 

I'd always get a whiff of fuel whenever i'd walk past the driver side of my 2004. Once i replace the gas cap then the whiff wafted away.

 

So...took a few pics. I see the potential issue where the smaller hose joins the fuel filler tube....notice the rust area and what appears to be holes at that joint. Also notice the unusual gashes on both hoses...maybe someone was working in the area and a tool slipped. Looks like each of two hose clamps were removed and not replaced. I just bought the truck a few months ago. Was a one-owner vehicle.

Also took pics of the other end of the hose at the top of the gas tank. Do not see an issue there although I could not get to the other side of that hose for a pic.

 

Have you checked the dealer to see if they carry the parts or if it was discontinued?

If your frame got replaced/sprayed it might explain what you see (missing hose clamps and slashes).

 

oh, boy....

 

Man what does the rest of your frame and fuel tank straps look like?

 

Actually, those pics are pretty much the worst of it. The frame does have some spot rust but all the metal is intact

 

On a Toyota parts site but have not been able to nail down an OEM part number for the fuel filler tube. It's an 02 4.7L AC 4x4 SR5.

 

Use the site in the bullet points here: https://www.tundras.com/threads/howto-use-the-toyota-parts-system-to-find-order-parts.113808/

It should be under the 'Fuel and Body' section, then search the page for "fuel", click thru to the 'Fuel Tank & Tube'.

Once in there, click on the 'open full size scheme' for each pic to find what you need. Click the number pointing at the part(s) you need.

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Thanks for the information. The website from the referenced forum page, first bullet (https://toyota-usa.epc-data.com/tundra/), did not provide the schema for the fuel filling system...unless I missed it.

However, using the autoparts.toyota.com site, I followed your guidance and I think it landed me on the correct part listing. It did not have a diagram but I looked for another part in that category that did to find the part.

I will confirm with a dealer before purchasing. I will ask them what "without Stay" means as well.

Thanks for your time and effort in providing this information.

 

Weird, I see all the filler stuff right here, as seen in my screencap above:

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Hmmmm, I see what happened. The category that site used for the fuel filler system is Body and Interior. That is not intuitive to me but that's where it sits, so I'm good now.

Below is the play by play when using the more intuitive (at least to me) Engine, Fuel System, and Tools category. At least there are just four possible categories for deploying the trial and error method.

 

Sorry, yeah, I had a typo above. I meant 'Body and Interior' but I said 'Fuel and Body', which isn't a category.

 

As it turns out, after talking with a dealer, Toyota doesn't supply that part anyway....even though the website lets you add it to the cart. They acknowledged the glitch.

 

You might want to check with Amayama or Partsouq. Sometimes you can score legit parts direct from Japan or UAE when they're NLA in the USA.

 

Thanks for those references...neither have the part but I like the user-friendliness of their webpages...hover the mouse over a part number in the list and the related number is highlighted in the schema.

 

Meant to close out this thread.....found someone on Ebay with a used fuel filler, pretty good shape. Took care of the leaking vapors and enabled a passing emissions test here in the DMV. Thanks for everyone's input.

 

Good to know.

I’ll have to take a closer look at those areas myself, although I did see fuel dripping out of my tank when full so maybe not the same.

 

Glad you got it sorted ... had fuel smells for a while before the slow leak code showed up. I thought it was just desert heat anomaly.

Turns out it was the seam on OEM rollover valve separated at seam. Took a few weeks to find as when you clear codes it took a week or two to come back.

I need to get a smoke machine then it would've been an easy find.

This was on first gen Tacoma