What's this pipe?

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Feb 4, 2013 | 11:03 PM

bpbyrne

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From: Austin Texas

What's this pipe?

Folks, I am chasing multiple issues, perhaps related perhaps not.

Issue 1) Running hot. (230 before my nerves kick in and I hit the heater & head for home). This happened relatively suddenly its a definite change. I am starting to think water pump, but am still doing my research.

Issue 2) Oil leak from high up on the passenger side head. Still working my way around with a mirror determining exactly where, but in looking for it I spotted this:

It is a rubber hose running along the top of the passenger side head. It had a foam cover which I could see oil near...in touching the foam cover the whole hose literally came off at my fingertips.

So, some questions:

- what is this hose? It looks like maybe an oil return line or vent line?
- why is it so loose? should there be clamps? Has the rubber simply been affected by the overheating above? It is soft and pliable to the touch...

Any input much appreciated.

Brian

Last edited by bpbyrne; Feb 4, 2013 at 11:09 PM.

Feb 5, 2013 | 12:14 AM

Bill Curlee

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Joined: Dec 1999

Posts: 32,910

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From: Anthony TX

CI 6,7,8,9,11 Vet

St. Jude Donor '08

Thats the Positive Crancase Vent hose. Its the VACUUM SUPPLY to the system. Look where it connects to the intake manifold. I bet your engine runs LEAN and ROUGH.. If it were me,, I would carefully inspect the entire PCV system and make sure that its all there and not cracked, deteroriated or modified the wrong way.

After you reconnect it, the engine will have to idle relearn and adjust for the correct AFR.

Bill

Feb 5, 2013 | 10:04 AM

bpbyrne

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From: Austin Texas

Quote:

Originally Posted by Bill Curlee

Thanks Bill - that helps. I will reconnect, disconnect battery to reset CPU and start everything from scratch.

Can you help me validate a few things:

- This is the vacuum supply for all vacuum operated devices?
- This should also be affecting the actuators for my AC/Heating right (another issue I am chasing)
- Should there be oil in this line? I am seeing evidence of it, and in fact I found this loose line because I was following an oil drip..
- This line was unbelievably loose..should I add clamps?
- Any issues I would be having with running hot should be entirely unrelated unless I am missing something?

Thanks again
Brian

Feb 5, 2013 | 10:28 AM

sean.b

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From: Colorado

Quote:

Originally Posted by bpbyrne

vacuum supply for ALL, no. if you look around the intake, things needing vacuum will suck it from the intake in various locations, though.

actuators.. not on the PCV line. again, pan around the intake, look for more random things disconnected. who the hell owned this car before you?

yes it's normal to have some oil in that line. thus the reason a lot of us run catch cans.

if it's loose, clamp away.

that wouldnt cause you to run hot. an idiot (such as one that'd leave that hose completely missing) may have done something, though. if you're hot, look @ thermostat and pump, as that's really all there is to cooling the car. check for hot hoses/cold hoses indicative of the thermostat not opening, and open the cap and look for signs of the water moving at all. only other thing it can be is the fans - they should kick on when the coolant temp is up there. i guess a bad temperature sensor, relay, or fuse could cause them not to. plenty of info online and here for troubleshooting running hot.

Feb 5, 2013 | 05:09 PM

bpbyrne

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From: Austin Texas

Quote:

actuators.. not on the PCV line. again, pan around the intake, look for more random things disconnected. who the hell owned this car before you?

that wouldnt cause you to run hot. an idiot (such as one that'd leave that hose completely missing) may have done something, though.

Thanks guys.
By the way there is no previous owner to blame here (!) - but in my defense the pipe hadn't been removed, it was just extremely loose on its connectors.

I'm bringing the car back from 6 months of neglect... divorce and car maintenance dont mix

Feb 5, 2013 | 05:11 PM

sean.b

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From: Colorado

Quote:

Originally Posted by bpbyrne

OH so you took it off for the pic, ok. I thought you were rolling around and noticed it was missing

Yea if that's loose, clamp it up. It has to be air tight, as it's a vacuum line, so do whatever you must to keep it as one.

Good luck with the car and the divorce.

Feb 5, 2013 | 05:22 PM

mchicia1

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Joined: Apr 2009

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From: Morrisville PA

You may want to consider the ls6 valley cover swap. It cleans up the engine bay as it gets rid of that line.

Feb 5, 2013 | 05:58 PM

Bill Curlee

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From: Anthony TX

CI 6,7,8,9,11 Vet

St. Jude Donor '08

The back of the manifold contains the aux line source for your vacuum reservoir and that is where the HVAC and AIR Pump get their vacuum source. The sensor is the Manifold Absolute Pressure (MAP) transducer:

Vacuum Line for the Brake Booster and vacuum reservoir supply:

Vacuum reservoir:

The HISS noise you hear is the vacuum bleeding off one of the damper door actuators on the HVAC air box.

Order a Catch Can to help collect the oil blow by from the PCV system. It will help keep some of the oil out of the intake.