Plenum vacuum hoses

[cactus]

Hi, Long time lurker first time poster. I had to sign up to ask this question because I have trawled the site and cant find a definitive answer.

On the back of my plenum, ( VT standard V6 ecotec '99) there are 3 fittings for vacuum hoses. The big one (around 12mm) goes to the brake booster, the little one (around 3mm) goes to the firewall for the heater control function.

Now, the problem is, there is another one (around 8 mm) that doesn't have a hose and I don't know what connects to it. I have blocked it off for now but I'm hoping someone can tell me what its for.

Would really appreciate an answer, or if someone can check their car because I've been searching for an answer for days.

Thanks

 

[K-BAGZ]

Fuel pressure regulator.

 

[cactus]

Fuel pressure regulator.

omg thanks. I cant believe I missed it. When I saw your post I went out to the car, couldn't see the hose but put my hand under the back of the plenum near the fuel regulator and sure enough, there is was.

The funny thing is I've been driving around like that for at least a week, since I changed the inlet manifold gaskets, I even asked my mechanic, he looked at it and said he didn't know and just block it off. lol Runs much better now.

Thanks again problem solved.

 

[K-BAGZ]

As the compare the market meerkat would say, SIMPLES!

Pleasure to help.