OK. So, 1987 Mustang GT. I put in a new tank, fuel pump, sending unit, etc. including new grommets and vapor valve, put some fuel in, fired right up no problems. Drove the car (over a few weeks) about 60-70 miles no issues. Last week I go to the gas station, put some gas in (Tank is fairly full after but I did not fill to the point where the pump shuts off), heading home and find out it's puking gas out the back end. I put up on the jack stands and drop the tank (ugh) and the only thing I find wrong is the vapor valve is not fully seated in its grommet and it's clear that this is where the gas had spewed from. My initial thought was that I'm a dumb-ass and didn't fully seat the valve when putting the new tank set up together so I clean everything up, push the valve fully into the grommet, put the whole shebang back together, fires up fine. I let it idle for 20 minutes while I check for leaks, no problems, not a drop. I take it out for a ride around the block, pull back into the driveway and puking gas again.
I suspect there is something wrong downstream of the vapor valve. Could there be a blockage or something that is backing up pressure in the tank and then blowing that vapor valve out of its grommet and hence allowing fuel the spew out???
I do not have an adjustable FPR, nor have I checked the pressure yet (need to rent a tester later this week) although I'm concerned I won't get a proper reading until I drop the tank again and reinstall the vapor valve completely.
And again, this is a brand new tank, new sending unit, new 255LPH BBK fuel pump, new vapor valve & grommet.
Any help would be appreciated. It will likely be a few days before I can drop the tank again...
I suspect there is something wrong downstream of the vapor valve. Could there be a blockage or something that is backing up pressure in the tank and then blowing that vapor valve out of its grommet and hence allowing fuel the spew out???
I do not have an adjustable FPR, nor have I checked the pressure yet (need to rent a tester later this week) although I'm concerned I won't get a proper reading until I drop the tank again and reinstall the vapor valve completely.
And again, this is a brand new tank, new sending unit, new 255LPH BBK fuel pump, new vapor valve & grommet.
Any help would be appreciated. It will likely be a few days before I can drop the tank again...