where does this go
Thread Starter
2nd Gear
Joined: Sep 2010
Posts: 2
Likes: 0
where does this go
I have a '96 C4 Grand Sport.The black tube with the gray plug came loose from somewhere. It is not an electrical connection. It appears to be some kind of vacuum plug as no fluid came out of it either.It is clamped down next to the alternator. I installed a throttle body by pass tube and just noticed it. I do not remember taking it off of the throttle body. Does anyone know where this goes? If anyone would like to see a picture of it email me at carlkrauss@comcast.net and I will be happy to send you one. Thanx for the help!
Thread Starter
2nd Gear
Joined: Sep 2010
Posts: 2
Likes: 0
I take it the compressor is towards the drivers side of the alternator-or to the right if you are looking at the car from the front. The wire with the gray plug will not stretch over that far. Maybe I am looking in the wrong place? Is Does it stretch under the alternator towards the compressor or does it go around the front of the alternator?
Le Mans Master
Joined: May 2005
Posts: 7,377
Likes: 2,297
From: Central Maryland
Sounds like it could be the vacuum inlet line to the Opti. If so, it's supposed to be plugged into a small hole in the intake bellows. Can you post a pic of the item in question?
Live well,
SJW
Live well,
SJW
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Le Mans Master
Joined: May 2005
Posts: 7,377
Likes: 2,297
From: Central Maryland
Yep, I know exactly what that is. It is the inlet vacuum line to the Opti. The photos show that your GS has a non-original intake bellows on it. That's why you can't find the hole where this fitting goes. The original accordion-style intake bellows had a hole for this fitting. You can either reinstall the original intake bellows, or drill a hole for the fitting in the part that's on the car now. Obviously, if you drill the existing part, you need to make sure you get ALL of the debris out of the intake tract before you start the engine.
I emailed you two photos that will show you how the factory set-up was implemented. You can clearly see the fitting going into the bellows just aft of the MAF.
You should get this hooked up properly. Right now, you are sucking unfiltered air into the Opti and then into the engine, and that's never good. It's also unmetered air -- it hasn't flowed through the MAF, so the ECM doesn't know it's there. The ECM wants to know how much air's going into the intake manifold, and this amounts to a vacuum leak.
Take care,
SJW
I emailed you two photos that will show you how the factory set-up was implemented. You can clearly see the fitting going into the bellows just aft of the MAF.
You should get this hooked up properly. Right now, you are sucking unfiltered air into the Opti and then into the engine, and that's never good. It's also unmetered air -- it hasn't flowed through the MAF, so the ECM doesn't know it's there. The ECM wants to know how much air's going into the intake manifold, and this amounts to a vacuum leak.
Take care,
SJW