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YOUR RESEARCH2004 C4S Oil Leak from corrugated tube? - please help!
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just normal wear and tear
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2004 C4S Oil Leak from corrugated tube? - please help!
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Leading evidence: 'just normal wear and tear' (1 discussions report identifying this cause; no attributable repair resolution). Across 1 matching discussions, the most frequently mentioned possible cause is 'just normal wear and tear' (1 discussions; 1 report identifying it and 0 suggest it). The most frequently discussed action is 'Replace vent hose' (1 discussions). For that action, 0 discussions report a resolution and 0 report an unsuccessful attempt. No action has an explicit, attributable resolution report under the current rules. These are forum reports and suggestions, not a confirmed diagnosis.
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Explicit resolution reports before identified causes, performed actions and suggestions. Within each level, matching component labels precede direct query mentions and inherited thread context; successful versus unsuccessful discussion counts, owner confirmations and independent discussion support determine order. This is not a probability of success.
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Suggestion · Original poster
Now trying to figure out how much harder it would be to change the vent hose on the car given it's a tip VS non tip.
2004 C4S Oil Leak from corrugated tube? - please help!
Replace with a new one
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Explicit resolution reports before identified causes, performed actions and suggestions. Within each level, matching component labels precede direct query mentions and inherited thread context; successful versus unsuccessful discussion counts, owner confirmations and independent discussion support determine order. This is not a probability of success.
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2004 C4S Oil Leak from corrugated tube? - please help!
Use heat shield pad behind, i'm a telecomm guy
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No successful repair reported for this finding.
0
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Unsuccessful attempts
1
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Explicit resolution reports before identified causes, performed actions and suggestions. Within each level, matching component labels precede direct query mentions and inherited thread context; successful versus unsuccessful discussion counts, owner confirmations and independent discussion support determine order. This is not a probability of success.
Discussions that contain suggestions
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Suggestion
Could you not unclip the pipe on the right bank and slide a length of heat shrink tube over the damage then shrink down with a heat gun , obviously being careful of any other piping and wires, maybe use a heat shield pad behind, I'm a Telecomm guy and use heat shrink for my job so used one on mine when I accidentally broke my pipe moving my inlet manifold in the garage and have repaired this way but mine is off the car, might save trying to change out that pipe with engine in car, I don't know how you would do it??
2004 C4S Oil Leak from corrugated tube? - please help!
Use heat shrink
Suggestion or failed attempt
No successful repair reported for this finding.
0
Reported fixes
0
Unsuccessful attempts
1
Discussions
Read evidence and context
Explicit resolution reports before identified causes, performed actions and suggestions. Within each level, matching component labels precede direct query mentions and inherited thread context; successful versus unsuccessful discussion counts, owner confirmations and independent discussion support determine order. This is not a probability of success.
Discussions that contain suggestions
1
0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.
0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.
Suggestion
Could you not unclip the pipe on the right bank and slide a length of heat shrink tube over the damage then shrink down with a heat gun , obviously being careful of any other piping and wires, maybe use a heat shield pad behind, I'm a Telecomm guy and use heat shrink for my job so used one on mine when I accidentally broke my pipe moving my inlet manifold in the garage and have repaired this way but mine is off the car, might save trying to change out that pipe with engine in car, I don't know how you would do it??
2004 C4S Oil Leak from corrugated tube? - please help!
Use heat shield pad behind, i'm a telecomm guy
No successful repair reported for this finding.
0
Reported fixes
0
Unsuccessful attempts
1
Discussions
Read evidence and context
Discussions that contain suggestions
1
0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.
0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.
Suggestion
Could you not unclip the pipe on the right bank and slide a length of heat shrink tube over the damage then shrink down with a heat gun , obviously being careful of any other piping and wires, maybe use a heat shield pad behind, I'm a Telecomm guy and use heat shrink for my job so used one on mine when I accidentally broke my pipe moving my inlet manifold in the garage and have repaired this way but mine is off the car, might save trying to change out that pipe with engine in car, I don't know how you would do it??
2004 C4S Oil Leak from corrugated tube? - please help!
Use heat shrink
No successful repair reported for this finding.
0
Reported fixes
0
Unsuccessful attempts
1
Discussions
Read evidence and context
Discussions that contain suggestions
1
0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.
0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.
Suggestion
Could you not unclip the pipe on the right bank and slide a length of heat shrink tube over the damage then shrink down with a heat gun , obviously being careful of any other piping and wires, maybe use a heat shield pad behind, I'm a Telecomm guy and use heat shrink for my job so used one on mine when I accidentally broke my pipe moving my inlet manifold in the garage and have repaired this way but mine is off the car, might save trying to change out that pipe with engine in car, I don't know how you would do it??
2004 C4S Oil Leak from corrugated tube? - please help!
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Counts describe captured discussions, not unique people or a diagnosis. Author identities are not reliably stored. Exact duplicate evidence is counted once across matching discussions; one discussion counts at most once per action/state. Multiple repairs reported together remain a combination. Suggestions and failed attempts do not establish a fix. Matches cover whole discussions and can include related faults, model variants and incomplete threads.
25 eligible posts · 0 unverified posts · 1 discussions match the subject in their title or opening post.
Rennlist: 1 discussions
0 evidence records excluded for query context · 0 excluded by outcome qualification · 0 adjusted by outcome qualification.
0 acknowledgements have no verified action link; they do not establish a repair result.
Generation: 20261026T113718Z · outcome-qualification-6. Deterministic extraction; no AI model inference. How we use sources
Hi all -
Went for a drive and came back to an oil leak and trying to figure out what it is.
Attaching a picture of a thick black corrugated vent line? When you look closely at it (close up picture) it looks like it has melted and is exposed and leaking oil. The corrugated hose is really long and starts in bottom right of engine and cuts to the back left rear of engine...really long.
What is this corrugated line and can it leak oil? What would cause something like this?
Other notes:
-Oil pressure sender looks clean and not leaking
-Don't know if this happened before or after the corrugated tube apparently melted, but car was throwing P0171 and P0174 in the days leading up to me seeing the oil leak and messed up hose
Thank you!!
thick black corrugated line. looks melted and exposed where the arrow is pointed.
black corrugated tube
That hose would be your AOS vent hose part #4 here. Great pic BTW. Yes, that is causing a vacuum leak and your CEL codes P0174 P0171.
I don't have a definitive answer as the what happened to the hose, but extreme heat would be my first thought. The hose is a PA12 material that doesn't really have a melt temp, it starts to soften at about 110C and continually gets softer and softer up to about 180C ( which some consider the melt temp)..
Could you not unclip the pipe on the right bank and slide a length of heat shrink tube over the damage then shrink down with a heat gun , obviously being careful of any other piping and wires, maybe use a heat shield pad behind, I'm a Telecomm guy and use heat shrink for my job so used one on mine when I accidentally broke my pipe moving my inlet manifold in the garage and have repaired this way but mine is off the car, might save trying to change out that pipe with engine in car, I don't know how you would do it?? That's a long pipe and quite fragile, mine was pretty new only a couple years old from my original re build and it still snapped like a twig, should be metal!
Band-Aids and bubble gum is not a fix. That hose should be replaced with a new one. If it is rodent damage (looks like fur/hair on it) it could very well be chewed up in other places unseen.
I've replaced that hose its not that bad to do - mine was touching the coolant level sensor and it created a hole in the tube over time.
https://rennlist.com/forums/996-foru...-aos-line.html
That hose goes to your oil separator. Generally end up having to remove the intake to replace it. It's been a while since I've done one but It might not be as bad if the car has a manual transmission. Should only be a few hours worth of work if it's just the hose you need and no other issue pop up.
The cause is just normal wear and tear. At the end of the day it's only plastic. It's effective for a long time but after enough heat cycles it just deteriorates like anything else.
It's possible, could explain why he noticed the oil leak suddenly. Like you said, good way to tell is if there's other signs like droppings, bite marks on the insulation, rodent **** smell,etc.
For a MK1 you'd need to remove the intake as the tube is not flexible for a MK2 as its corrugated you don't need to remove the intake - just need to remove the air box, tb + plenum. Make sure you get yourself the 944 cable tie (if you're pedantic) or just a long one if you're not - as you'll need to cut the original that holds it to the resonance plenum/tube.
Snails eat oily plastic? Wow!!! Or, do rats/mice eat snails? I'm trying to make the logic leap here...chewed plastic > empty snail shells...C'mon people, throw me a bone here, okay? (in my best Dr Evil voice...)...
OK, the suspense was killing me, the correlation of rats to snails, to solve the mystery, (yes I am obsessed with failure analysis), google provided a plausible answer.
Yes, rats do indeed love to eat Snails and Slugs as a delicacy. So, the plausible answer as to why a rat would chew on oily PA12 Polyamide plastic, is that a Snail or Slug crawled around on the AOS breather tube and left a yummy trail..lol
FWIW rats also eat wiring insulation due to the cornstarch is an ingredient in the insulation, they sometimes even eat through the copper core !!
COVID-ly late response...bu THANK YOU ALL from a Porsche newbie.
Well, we DID find some rat poop and some insulation eaten away. The rat poo was deep within the engine and could only see it with a micro camera. Now trying to figure out how much harder it would be to change the vent hose on the car given it's a tip VS non tip. Any thoughts? Local shop quoted me $1,300 for vent hose and AOS.
I thought that looked like rodent fur stuck on that chewed up hose...
After doing the AOS twice on a MT, I'd seriously consider just having it done at that price.
Got the AOS and vent tube replaced and no more engine oil leak, thanks for guidance! Dang rat. Work was done from the top.
That said, now it's leaking red oil which was not present before. Anything done while they changed out AOS/vent tube that could cause this?
SMH. Thank you!
Im thinking coolant? Maybe a little oil mixed in. Its really hard to get to the aos hose port on the passenger side and they may have pulled the coolant hose. i would remove the air cleaner and look around.
i was thinking that too but it seems like its the wrong color. I just flushed mine and it was on the green side of black and the new fluid was clear green. I guess someone could have used the wrong fluid or the die colors may have changed.
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