1994 850 Turbo Wagon

The last four times I have refueled, almost as soon as I get back on the road the car starts to loose power and eventually dies. It'll start back up but won't hold an idle. It throws all kinds of codes having to do with cylinder misfires and once threw a Fuel trim at limits at idle. I'll let it sit overnight and it will start up, hold an idle and after a few miles run just fine. I'll clear the codes and they will remain clear until the next refueling, then, blamo, same thing. I've been consistently letting it get to a quarter tank or less before refueling to keep variables the same. The fuel filter was pulled and poured a glass full of clear clean gas. It doesn't seem to be a fuel delivery problem, rather the engine seems to flood. It spews black exhaust that smells rich with gasoline while it's struggling. Next morning, fine. Theories?

It sounds like you are over filling the tank and sucking fuel into the evap canister through the vent system. Does your state require that rubber gizmo on the pump nozzle that prevents vapors from getting into the atmosphere? If so, maybe that is forcing fuel into the vent. It must be something to do with filling up.
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Tom 69-1800S, 72-1800ES, 96-850T,2000-S70 GLT-SE

Does it do the same thing if you just take the gas cap off for a few minutes and then put it back? I think I remember reading here that 93's and 94's can have cap venting problems. Also maybe try adding a few gallons shy of a full tank.

I'll try those things. It does have a heck of a vacuum when I release the cap. I've been told that the cap doesn't vent these tanks but rather the EVAP system does.

I think FIXIT is on to something. There should not be a vacuum when removing the gas cap, well, maybe just a small amount.
New gas cap could be in order???

Klaus
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The 164 has a new home, all I am left with are a 95 854T and a 98 V70R :)

The symptoms sound like raw gasoline is being drawn up through the charcoal filter into your manifold. When you fill the tank, do you give it extra gasoline after the pump automatically shuts off? That could cause gasoline to flow down the vapor tube to the cannister.
It not happening the following morning throws me for a loop.

Klaus
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The 164 has a new home, all I am left with are a 95 854T and a 98 V70R :)

I don't top it up. Maybe next time I'll fill it to less than full and see if it does the same thing. Thanks