Can someone identify these parts? Vacuum leak detection

Sylvester

Member
Hi guys, I've been dealing with MAP sensor issues, and while sorting the other possible causes, I've patching up even small cracks on breather hoses, to avoid vacuum leak.

I don't wanna miss of it, so I've read you can blow cigarette smoke into system, lightly as over 1PSI can damage engine parts, and that should show hidden leaks, even Throttle Body seals, etc.
I'm not a pro, so I rather not use propen/starter fluid as other options.
Most people recommend the BRAKE BOOSTER HOSE, which on is it on the A2 1.4 petrol? Any other info is appreciated.
 
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Can someone identify these 5 parts? Thanks
 

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Isn't 3 the air intake pipe from the trumpet behind the oil filler going down to the filter box in front of the front wheel arch ; thereafter the air goes through the filter and then up and along the black plastic pipe that climbs and goes rearwards towards the MAF (this part visible above the red arrowhead?).

If this is a BBY, is 4 one of the pipes that goes to the crankcase oil scavenger thing down the back of the engine block?
 
Isn't 3 the air intake pipe from the trumpet behind the oil filler going down to the filter box in front of the front wheel arch ; thereafter the air goes through the filter and then up and along the black plastic pipe that climbs and goes rearwards towards the MAF (this part visible above the red arrowhead?).

If this is a BBY, is 4 one of the pipes that goes to the crankcase oil scavenger thing down the back of the engine block?
Hi Robin, it's an AUA 1.4 petrol, from what I've read it only has MAP sensor, cheers.
 
1&2 hot coolant heater hoses
3 charcoal canister pipe
4 cold air feed intake going to air filter box
5 looks like the underside of the plastic pipework unit that slides onto the throttle body.
Did you check out the thread by sarge ?
I've had a look for it but can't remember what it is called.
He details that the pipe that rises from the back of the engine from the oil separator can wear through because it rubs on one of the pipes on the engine firewall. It's repairable using self amalgamating tape.
??
 
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1&2 hot coolant heater hoses
3 charcoal canister pipe
4 cold air feed intake going to air filter box
5 looks like the underside of the plastic pipework unit that slides onto the throttle body.
Did you check out the thread by sarge ?
I've had a look for it but can't remember what it is called.
He details that the pipe that rises from the back of the engine from the oil separator can wear through because it rubs on one of the pipes on the engine firewall. It's repairable using self amalgamating tape.
??
Thanks for pointing out the parts.
Yes I've read it and changed them already last month, details with pics in my profile, the oil separator looked like covered with cooked butter inside, hoses had tiny cracks still patched them up, but nothing really changed, actually idle got even worse.
I'm gonna smoke-test the engine to check for leaks, then start to order parts, not sure which hose to use, but I'll figure it out. Cheers
 
I had this very same problem.
I replaced these cheap bits first.

Egr valve and all associated metal pipe gasket seals.
Injector upper and lower rubber o-rings.
Inlet manifold to cylinder head rubber seals.
Exhaust manifold metal gasket.
Cat to exhaust metal gasket
Throttle body cleaned and new metal/rubber gaskets
Fuel filler cap.
Both engine oil filler cap rubber seals.
The dip stick rubber o rings (drilled a hole in the slam panel and used a zip tie to hold the dipstick firmly shut)
The dipstick pipe o rings
Oil filler pipe o rings
Brake booster vacuum pipe and check brake booster seal behind the 1 way valve
Map sensor o rings
Upper and lower oil separator seals (if yours is that design)
Replaced worn out hoses. Including fuel pressure regulator hose.
Removed inner drivers side wheel arch lining clean and ceck charcoal canister for damage and its hoses.




More expensive parts changed were
Cambelt kit - the cam cover has to come off to do this. 1 spark plug was sat in a pool of oil. Cam cover sealant had failed.
Oil filter and rubber seal
Fuel filter
Spark plugs
Bank 2 lambda cheap eBay one
Ignition coil pack
Battery

Went from slow to go.
Lighter and quieter than my tdi and great to drive.
Sorry if I have repeated jobs you have already covered.

Good luck
 
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I had this very same problem.
I replaced these cheap bits first.

Egr valve and all associated metal pipe gasket seals.
Injector upper and lower rubber o-rings.
Inlet manifold to cylinder head rubber seals.
Exhaust manifold metal gasket.
Cat to exhaust metal gasket
Throttle body cleaned and new metal/rubber gaskets
Fuel filler cap.
Both engine oil filler cap rubber seals.
The dip stick rubber o rings (drilled a hole in the slam panel and used a zip tie to hold the dipstick firmly shut)
The dipstick pipe o rings
Oil filler pipe o rings
Brake booster vacuum pipe and check brake booster seal behind the 1 way valve
Map sensor o rings
Upper and lower oil separator seals (if yours is that design)
Replaced worn out hoses. Including fuel pressure regulator hose.
Removed inner drivers side wheel arch lining clean and ceck charcoal canister for damage and its hoses.




More expensive parts changed were
Cambelt kit - the cam cover has to come off to do this. 1 spark plug was sat in a pool of oil. Cam cover sealant had failed.
Oil filter and rubber seal
Fuel filter
Spark plugs
Bank 2 lambda cheap eBay one
Ignition coil pack
Battery

Went from slow to go.
Lighter and quieter than my tdi and great to drive.
Sorry if I have repeated jobs you have already covered.

Good luck
That is a lot of work, well done for that!
What I'm trying to do next, is to see if there's any vacuum leak , so I plan to smoke-test the engine. I got all the things I need for that, but not sure which hose to use, so the smoke goes through the entire system.
Shall I just hook it up to the top of the manifold, right after the airbox hose jubelee clip? (Red arrow in pic). Thanks
 
Initially would it not be better to run the engine with all hoses connected and blow the smoke around the engine bay. A vacuum leak would show as smoke being sucked it. Then with engine off pick the point of entry ( perhaps several splitting the systems down ) and in this case you are looking for smoke escaping INTO the engine bay.
 
Initially would it not be better to run the engine with all hoses connected and blow the smoke around the engine bay. A vacuum leak would show as smoke being sucked it. Then with engine off pick the point of entry ( perhaps several splitting the systems down ) and in this case you are looking for smoke escaping INTO the engine bay.
Yes I was thinking the same, but if there's a leak in the back of the engine, I might not spray enough to show it or can't even reach it, then I think it's all good, but actually it's still leaking. I'm gonna do it this weekend, just gonna the air intake, if nothing, I'll try the one on the throttle body too. Thanks
 
Did you find the leak?
Hi, sorry to get back late, I didn't see the notification.
There was a lot of tiny splits on some of the hoses, mainly the ones just behind the engine, you can only see them from underneath the car, with under tray off.
If I recall it correctly the main issue was the dirty MAP sensor, I had to buy it a few times as they just didn't seem fit properly, I can't exactly remember as I've been dealing with other issues a bit way too often, but I might ended up putting the original sensor back after cleaning it, also I'd changed the oil separator, which was full of yellow gunk, plus I'd cleaned the inside of the vacuum hoses as they were a bit dirty inside. That seemed to cure that issue.
 
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