So iv`e been working on the car since last summer..fixing some minor stuff like metal decay and some electronics stuff, ill list most of my actions if needed...

A few pointers about the car that might help:

- S5 91 T2.
- Streetport Stage1.
- New downpipe with O2 and new tubing with a racing cat in the middle and Racing Beat Y pipes.

What i did (slooooowly) during this winter:

- Rewire blinkers and hazards
- Connectd O2 in the correct harness-plug
- Connected BAC-Valve onto the correct plug (Seen sitting alittle lower and to the left of the Intercooler)

The Problem: Reference to the video below!

Sounds like a hissing airy sound dont u think? And everytime that sucking/blowing sound came the engine would instantly REV down as if being choked or as if the pressure system (Vacuum leak)isnt as it should be?

NOTE: The O2 sensor and BAC valve connectors were not connected AT ALL before and the engine ran fine then..

My Suscpisions:

1. While changing the gasket between the upper and lower manifold i managed to make a small rift in it..now i cant remember if i got a new one or just placed the rifted one as well into there as possible...this was 2 years ago and i was using the car at winter then. But this winter its been sitting for maybe 8-9 months since last summer actually..could it be the gasket finally gave in?

Below the BAC-Valve connector the is a hose about 10cm in length which is only sitting there open...like..its connected to the blockthingyding and hangs in free air..where does this hose go..couldnt find it at first glance in the manual..ALSO...u hear a hard kind of fast hiss as if it was from a mini BOV when i stop the engine...which leads me to believe even further the problem is a Vacuum issue.

What am i gonna do about it? :

Check the gasket as this is an easy fix and ill just replace it anyway since i got 2 more laying around here somewhere...If this doesnt fix the problem im stumped for now..back to the thinkercap!


VIDEO->

 

That hose not being connected is not only your hissing noise, but also the reason your engine is dying. It's unmetered air, giving the O2 sensor a lean condition, bogging the engine down. Looks like the stock location for it is between the turbo and intercooler. Connect that hose and see what happens.

 

Its already connected...it wasnt before...the O2 harness plug was connected to the P/S oil pressure switch before that...probably a faulty connection made by the dude who installed the engine the first time...the BAC valve connector wasnt hooked up before either but is now....

 

The hose I was referring to is the hose underneath the BAC. Looks like in the video that it's not connected to the charge pipe. However, I just watched your video. Sounds like you need to adjust the throttle position sensor first. Then if it's still surging, hunt down any vacuum leaks with some carb spray while the engine's running.

 

yeah i know..i was referring too your comment about the O2 sensor when i said it already connected..I cant find where this loose hose needs to go in the manual thou

 

Page 8 (or F2-6)

http://www.rotaryheads.com/PDF/2nd_g...tems_turbo.pdf

It connects somewhere between the outlet of the turbo and the inlet of the intercooler.

 

Thanks mate ill check it out..i never had this problem before i connected the BAC valve plug and O2 sensor plug into the right connectors, car still has a basemap from a frew years back

 

btw...Im getting a high reading on the knock metering on my PFC, im guessing a high knock value is a bad thing? I remember it going almost full up on the scale on the higher RPM`s before i put it in storage this winter..