Possible cause for flooding: Purge valve/charcoal canister?
 

I doubt this happens often, but it's something I ran across that should be at least looked at in chronic flooding situations.

I got sick of breathing raw gas fumes from the gas tank vent on the passenger's side firewall. Emissions removed, no charcoal canister, they just vent freely. And, yes, I've confirmed that it's coming from there and not my pulsation damper or anywhere.

I ran a small vacuum line from the nipple up into the front of the engine bay, and decided that the intake snorkel looked like a good place to vent gas fumes. So, I did, and things were fine - I didn't smell a bit of gas the entire trip. However, when I tried to start the engine, it was flooded. My car doesn't normally flood, but it does it on occasion, so I cycled the fuel pump cutoff, started the engine, and went on my way. However, the *next* time I stopped, I also flooded. I took the vent out of the intake, and vented it down towards the ground. No more flooding!

The reason I offer this random story is as follows: The charcoal canister normally is purged into the intake system under normal driving. It's done at a high enough RPM that it doesn't affect anything. However, if the purge solenoid is stuck open, it's conceivable that enough gas vapor gets through the canister to cause a flooded condition when trying to start the engine.

This may or may not be something that ever happens, but given my experience with routing the fuel tank vent into the intake, it's at least a possibility.

Keywords: Flooding fuel tank vent

-=Russ=-

So would you have pics on how you have it now I resolved a flooding problem by buying brand knew injectors but this sound interesting so the line to the black caaster you just vent that into the air

I have a fairly complete emissions removal. The gas tank vent is currently running through a vacuum line to the front of the engine bay, and down to the bottom of the front space, venting under the car.

I don't think this is a common cause, but it's at least worth considering if nothing else works (including new injectors).

-=Russ=-

interesting, i will have to try it as i have constant hot start flooding issues but the engine runs perfectly aside from this issue. i assumed it was the injectors as i haven't had the time to have them serviced and never thought about the evap vapors being an issue.

i'm going standalone in a week or so so this is the best time to check this.

Interesting theory...thanx for dropping that bit of data.


-Ted

I would consider this far more likely to cause problems with a cold engine than a hot one. Fuel vapours are not going to flood an engine, and in a hot engine they will stay in vapour form. But when the enigne cools and the fuel vapours condense back into a liquid form, it's possible flooding could occur.

BTW, there's no purge solenoid, just a vacuum operated valve. :)