Just changing my flame trap this weekend and although I often check the hoses from the Throttle body brass nipples , I never checked the hose that comes out of the intake manafold and runs to the small nipple on the Flame Trap housing.

Well, it was major clogged. I couldn't even clear it with a clothes hanger.

The engine has always run fine. Now that the hose is clear, I think I feel a little more responsivness in the accelerator. Then again, the car always feels like it runs better even after a good cleaning and waxing let alone an engine issue.

QUESTION: With the path going from the intake manafold to the Flame trap which runs to the throttle body, there is no Engine pressure difference so why does this hose exist AND is it possible that the throttle could be more responsive?
Thanks
--
'75 Jeep CJ5 345Hp ChevyPwr and two motorcycles: it wasn't Volvos safety , it was Longevity that sold me

At idle there is max difference in pressure between manifold and any point upstream from the throttle. That hose provides a path for that vacume to maintain negative crankcase pressure. By the way be sure to check that small nipple as it frequently clogs too. I don't think that hose could affect performance. The whole purpose of life for the flame trap and associated plumbing is to vent the crankcase and burn the fumes. It's an emission thing.

Thanks dave, The nipple was OK, I made sure before putting the hose back...thanks
--
'75 Jeep CJ5 345Hp ChevyPwr and two motorcycles: it wasn't Volvos safety , it was Longevity that sold me

I think it provides vacuum to suck the vapors at low rmps or at idle.

I have been working on the same hose. I think it comes into play above idle. I don't think the small hose can supply eneough vacuum to operate the system correctly. The question I have alont the same lines is how is the large hose connected to the intake? I thought there was a nipple in the hose , but I cut into the connection area , and nothing but hose inside. I believe the hose end has a gromet made into the hose to seal it. I tried to look into the intake , but at the time had no mirror , and could not feel a thing. Any ideas ?

Eck Sheppard Portsmouth, Va. 81 242