jns

I noticed the vac. operated valve on the exhaust of my 951 has no hose on it. I presume that valve is to help warm up the engine by blocking off exh. until it warms up. Is it required to be operating for a smog check? Is it normally open and flowing exh.? Will leaving it disconnected cause any problems? Thanks.

special tool

Where is this valve?

awilson40

I think you are talking about the wastegate...no dont disconnect it

Porsche-O-Phile

Disconnect wastegate line = bad things happen.

jns

This valve/gizmo is located downstream of the crossover pipe. If the exhaust were like a Y-shape where the upper left goes to the turbo and the upper right goes to the head. the valve is on the lower part of the Y. Comprende? It has a little accordion shaped section underneath it. Where does the vacuum line come from that goes to this thing?

Porsche-O-Phile

It sure sounds like the wastegate to me. The line goes along the firewall and up underneath the back of the intake to the cycling valve (CV), a small round little plastic thing with three lines (including this one) attached to it. The other two go to the J-boot (in front of the turbocharger) via piping under the intake manifold and to the "banjo bolt", a hollow bolt to allow air to pass through; it's on the hot side intercooler pipe, also by means of plumbing / piping located under the intake manifold. Seriously, if your wastegate line is unplugged, bad stuff can happen with a quickness. Your car will be ungodly fast - for about 3 seconds - before the cylinder walls rupture if you go full-throttle with it.

jns

Thanks for the info. I wasn't sure if it was the wastegate since the wastegate on an 87 Conquest TSI I had wasn't so far from the turbo if I remember correctly. This car also has an aftermarket blow-off valve mounted and I will be plugging off the hose connection under the throttle body based on what I read on a search. I haven't driven the car except for driving it into the garage so I could work on it since I got delivery of it from a transport company. I wonder why that wastgate hose was disconnected?

special tool

To give more boost

jns

Doesn't sound like a good plan to disconnect the wastegate to get more boost at the expense of a blown engine due to overboosting. I just hope the wastegate isn't faulty.However, as I learned from here, this would be a great excuse for an upgraded wastegate if it's bad.

special tool

You are right, it is not a good plan.