1989, 3VZE, Auto, 4x4

When I decelerate with the windows down I get a decently strong fuel smell in the cabin. I've owned the truck since 2019 and put 7k miles on it and it has done this since I bought it.

I first thought it might be because of holes in the muffler so I replaced the exhaust. Then after researching here I thought it might be the fuel pulsation damper so I replaced that. I've also checked that the vacuum lines to the charcoal canister were clear and they were. I just dropped the tank to see if I could see any noticeable leaks or cracks in the filler neck. Nothing has worked so far.

An interesting detail. If I fully tighten the fuel cap and drive up a long steep hill the engine will die from fuel starvation. I can get out and crack the cap and hear a strong vacuum release. I just replaced the cap with an OEM one but haven't had time to test if this is still the case but the fuel smell persists.

TIA



​​​​​​

 

The evap system? That controls a lot of the vacuum in the tank, I believe. There's the evap cylinder in the engine compartment, and lines going back to the fuel tank. Check the FSM for test procedures. Pretty easy, IIRC.

Good luck!
Pat☺

 

The fuel cap allows air in, but not out. If the air-in part was clogged, fuel starvation is a definite possibility. I'm not sure how that would lead to fuel smell, though.

When fumes build up in the tank, that's the job of the evap system. https://web.archive.org/web/20100326...76evaporat.pdf As 2ToyGuy hints, that's worth a look. There is a line from the evap canister to the carb, via the TVV (Thermal Vacuum Valve). The TVV is notorious for having broken-off plastic nipples (it's in a hellish environment). That could be your fume leak right there. Or, the TVV might not be opening. Or, a prior owner said "duh, what's dis?" and just unhooked it.

The Fuel Pressure Damper was a good guess, but you can test your work directly. Pressurize the fuel system with the Fp to B+ jumper, and feel around every fuel line (you don't want to be reaching in there when the engine is hot).

 

On a simple note and probably not the issue but my 22RE had a tiny tear on the bracket on the fuel filter, it was barely seeping out and drying so I couldn’t see it, but the smell in my cab drove me nuts. I think yours is under by the torsion bar?? Just a thought if you haven’t taken a look see

I do hope you get it sorted though, gas smells drive me absolutely bonkers!!!

 

thank you all for the advice. I'll check the canister per the fsm, I'll double check the tvv which I inspected while changing the damper, and also the fuel filter and report back.

 

Thank you so much for the information.