Rough starting after fueling up

Hi All,

Each time I fill up I have a rough time starting afterwards, I have to keep the key turned for 10 - 15 seconds and tap the gas pedal a bit to get started. Only happens after fueling up, any thoughts as to what I should look at to deal with this?

2001 Base Boxster

Thanks,
-Eric

it almost has to have something to do with evaporative emissions - vacuum maybe?

Very strange, to me.

I suppose it could be stirring up dirt and blocking the fuel pick-up - i'm grasping at straws.

Grant

Grant

gee-lenahan-at-gee-mail-dot-com

Is the fuel filter easy to replace? I don't know where it's located.

Quote
ericp
Hi All,

Each time I fill up I have a rough time starting afterwards, I have to keep the key turned for 10 - 15 seconds and tap the gas pedal a bit to get started. Only happens after fueling up, any thoughts as to what I should look at to deal with this?

2001 Base Boxster

Thanks,
-Eric

then I suspect there is something wrong with the fuel system vapor recovery system. Part of its job is to as the fuel level rises in the tank displaced air/fuel vapor is supposed to be vented to the canister, but no liquid fuel. If this system is allowing liquid fuel to get into the canister then at start up this can result in a overly rich mixture to the engine.

If you tell me if you stop short of starting the engine and the exhaust (or in this case the air expelled by the cranking engine) smells heavily of gasoline and if upon starting the engine emits a dark cloud of exhaust that smells heavily of gasoline this reinforces my suspicion the vapor recovery system is at fault.

Have you experimented to see if this behavior is not present if you say fill up short of a full tank? Also, I trust you do not top off the tank filling the tank to say the brim of the filler tube? I have found with the fuel nozzle turned nearly upside down the fuel nozzle's automatic shut works very consistently to shut off fuel delivery before overfilling and shuts off with the fuel at the same level every time so fuel mileage calculations are accurate and not affected by variations in the amount of fuel added per "fill up".

OTOH, if you tell me that while cranking the engine and with *no* throttle pedal action the engine spits back through the intake -- you may have to give a listen at the air intake vent while someone else cranks the engine, or just open the driver's door and bend an ear towards the vent -- then I'm thinking a fuel supply problem is involved.

This points to among other things the fuel filter, if one exists in your car. For instance my 02 Boxster has no serviceable fuel filter. The "filter" is the fine mesh screen that is part of the fuel pump housing through which the pump pulls fuel.

If your car has no serviceable fuel filter then the fuel pump has to be considered. My experience is these fail outright but there have been some reports of these acting up some before failure that one has to consider a misbehaving pump a possible explanation.

Thanks Marc,

I will test your theory about filling up as well as inspect lines, etc... I never top off when I fill up, as soon as the nozzle clicks I stop.

-Eric

I fueled up a week ago and only put in 1/2 tank. Started up, although seemed to be slightly rough. Then filled up a few days later and had the issue first reported where it was hard to start. I am believing more in the vapor collection theory as all other starting is fine without issue. I will inspect the hoses and such to see if I can trace it.

-Eric