Pontiac Owners Club UK

Hi all,

Im just wondering if anyone here has removed theirs and what the car is like ? the problem ive got is, ive never had one on my car, and the metal pipe that goes from the tank to it in the engine bay has been capped off. This has never been a problem until last year when i started smelling petrol. After a root around i found it was the filler neck on the petrol tank that was leaking.

So before fixing that everytime i took the petrol cap off i got no hiss, no pressure in the system. After i fixed it i get a huge whoooosh when removing the cap now, too much pressure ?

Im wondering if i need to get a vapour canister and try putting it all back together to keep the pressure down a bit, OR !.....replace my non vented petrol cap for a vented one and hope that does the same sort of thing ?

the hiss will be vacuum not pressure i would have thought. as the petrol is sucked out by the pump, the non vented cap creates a vacuum which is only release when you undo the cap. This happens on both my daily drives so i wouldnt think its an issue.

we took Davids one out years ago to make room for a cold air intake
ran and has run fine ever since

hmmm, im just worried theres too much pressure in the system though. John did you cap the end of the pipe off too ? and does Davids let out a huge whoosh when he undoes the cap at the petrol station ?

I will have to check if its vacuum or pressure releasing Ian as i never thought of it that way, it just sounds like its letting a load of air out. I think im getting consious of it now ive got the new engine in and it wont be long before im ready to fire it up

didn't cap them, just left them connected to the top valve (this unclips from the canister

ah right, i havnt got any of the assembly, i literally have a metal pipe that just stops near the steering linkage and thats it, the whole lot had been removed

i removed all mine on red just blocked up the vacuum lines was fine smelt less than it did before

as paul said, as long as the vac. pipe from the engine is blocked it will run fine

Just just leave it the way it is then, sounds good enough to me, i just hope this increase in vacuum / pressure noise when undoing the petrol cap is normal then

they all do that a bit mine did never let me down so was all good

All reassuring comments then !

Maybe im just not used to the big whooosh noise as it had obviously been leaking for ages, it used to let off a hiss when taking the cap off then it eventually stopped, no doubt as the crack in the filler neck got worse, so the car has probably never had a totally pressurised fuel system in the 10 years ive had it !