Wben I fill tbe tank and today I only had1/3 of a tank, windows closed a/c on I smell gas! I have already removed and repaired the tank and there is no gas smell in the trunk or engine compartment I cant figure where it could come from? And the smell seems to come from the a/c vents. Any suggestions?
David …
My first guess would be a very small leak around the top of your gas tank. But if you open up the trunk after the car sits overnight and you DON’T smell anything … then that’s not very likely the problem.
If you have a gas smell coming through the a/c vents it HAS to be coming in through the two fan assemblies, there is no other way it could enter the a/c system. In the “recirculation” position the fans draw air in from under the dash inside the car so if you don’t smell any gas in the cabin that can’t be the answer.
In the “fresh air” position the fans draw the air in from outside the car under the scuttle at the base of your windshield wiper. So that is a possibility, but only if you are operating the system in the “fresh air” mode. But you say you don’t smell gas under the hood?
Try operating the a/c in recirculate and see if the gas smell coming out of the vents goes away.
I live in southwest Fl. There are 2 settings I use, off and max cool, recirculating inside air. Thats what doesn’t seem to make sense. How could gas fumes get in? Sometimes it’s so bad I have to open windows to get rid of it, and then it seems to stop for no reason.
David …
First you have to absolutely eliminate any possibility that the gas smell is coming from your gas tank even though you’ve just had it repaired… This is a very common problem as you are well aware.
Once you do the trunk test then moving forward you need to check the fuel tank fittings under the car. While you’re down there also check the fittings on your external fuel pump and the fuel filter.
From there going forward the fuel travels to the engine bay via stainless steel lines so the possibility of a leak there is remote but possible if somehow they are damaged
The fuel smell coming out of the a/c vents in the recirculation mode almost has to be a result of the smell being in the cabin air.
No smell in the trunk, onward and forward! Fyi I did the tank repair myself but luckily no leaks in the trunk, I have noticed the fuel filler door open on occasions, possible source?
David …
As long as you have the gas cap on tight the position of the filler door shouldn’t make any difference.
I know it’s still very warm in SW Florida but try driving around with the A/C off and the windows up. Do you still have the fuel smell inside the car ? If not then turn on the A/C and see if the smell then returns.
I suspect that even though you’re driving with the system in “recirculation” mode one or both of the fan door control vacuum actuators have failed or no vacuums is being sent to them. If that’s the case the doors end up in the default “fresh air” position, which is the only way the gas smell could enter the A/C distribution system.
When I rebuilt my system I found one fan assembly’s vacuum actuator not working and the other assembly’s vacuum actuator was in fact working but not getting any vacuum … so it’s definitely a possibility !!
The problem is intermittent, happened a couple times, 45 minute drive, shut down for 15 to 30 minutes then restart and shortly thereafter the smell started, open the windows then it seems to go away. I checked both the trunk, and the hood with no smell at either place but stinks in the car, trust me, if it bizzare or not possible it will happen to me! Thanks for the input as this one has me really baffled.
Don’t have anyone smokin’ in there💥 check fuel lines in engine bay, connections, split lines that will leak only under pressure.
I HATE INTERMITTENT PROBLEMS !!!
Really, rather than have my engine running rough every third Sunday I’d rather have the &%#$ thing fall out of the car so I’d know right away what I was dealing with.
OK, I keep coming back to the fuel tank. Think about it, from your external fuel pump forward everything in the fuel system is under pressure with the pump running. Somewhere around 35psi i seem to remember. So if there’s a leak there it should be obvious after the car has been running a while and it wouldn’t be intermittent.
The tank however is not. My advice would be to remove your spare tire and carpeting and have a sniff around the top of the fuel tank after the car has sat overnight. As I’m sure you know when the tank leaks in that area you can really smell it in the cabin.
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Oh I hope it’s not the fuel tank, don’t want to pull that again! I did build a new panel behind the spare but the filler neck side is somewhat exposed.
I am thinking of pulling the whol backseat for a good interior sniff in that area.
David …
“My advice would be to remove your spare tire and carpeting and have a sniff around the top of the fuel tank after the car has sat overnight.” … I still think that’s a good idea.
If you “top off” the tank when you fill up, the gas can sometimes spill along the vapor line to the charcoal canister. Then you have a gas smell until it clears up.
Don’t top off the tank! 
I give up for now. When it smells I open all the winows for 5 or 10 minutes and then it’s gone.
GIVE UP … I think not sir.
Just make a temporary strategic retreat and refocus your attack.
I STILL believe that if you remove your spare tire and carpeting and have a sniff around the top of the fuel tank after the car has sat overnight that you’ll find the culprit is at the top of the tank.
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Well I did take the rear panel off and all looks good(this 1989 has no top hat on the tank) but I did notice the cabin vents into the trunk through the rear cabin deck,kind of odd, but no fuel smell. I will top off the tank and recheck, haven’t given up just regrouping !