Hi all,
Made a couple of posts, but I’m after some advice to lean on the experience here.
Firstly I’m a new member, so a bit of intro / background.
Just bought a A3 1.8TFSI S Line, to replace my Merc that someone decided to write off to save their brake wear...
Bought it cheap with a few obvious problems, which i hoped to pick through and give it a new lease of life... The exterior is in pretty good nick for the ages, as is the interior... its on 99,000miles
So i have ticked through the following little jobs -
Rear discs and pads
Repair the drivers interior door handle, spot of drilling and tapping
Front washer jets replaced as partially blocked, done, upgraded to fan type
Rear washer jets replaced as blocked
New wipers, just to cheer myself up one day
New battery in the remote - now she unlocks as well as locks! - the first help this forum provided
New front undertray
Now then.. the main event however - engine oil leak.
When i first purchased, this was pretty obvious, but i went ahead knowing that i could happily deal with most leaks, I’m an auto engineer by trade and have rebuild engines and done my own repair work for the past 20 years...
Perhaps i bit off more than i thought, as the first few days of ownership it was smoking at traffic lights etc.. i was nervously watching the oil level until the weekend..
So first up, the engine bay was drenched, looked like it had been leaking a while and covered most areas, so i spent a day going about some obvious easy wins, and then cleaned everything down so i could then later identify any further leaks.
Sump off, very clean indeed, pick up spotless, so resealed and refitted, starting to think someone’s been in here already..
Cam cover, i could believe that it had a weep, so popped that off and the cam chain cover vac pump etc.
This is where i found a missing rocker/follower!! (I popped a rushed thread up about this before!)
It had been spat out and was found in the well between 3 and 4 plug..
So a few days waiting for the TPS to get a new follower and hydraulic equaliser in, and i popped that all back together, resealed cover, new seal for cam chain cover, new vacuum pump seal, fuel pump follower inspected and all ok, cam chain tensioner was a letter revision and in good condition, chain stretch not severe..
All going well..
I noted that it had a new PCV valve a few months before buying, so double checked all was still ok with that - all working as it should be, nice taste of oil in the mouth, job done. Oil filler off..
HMMMM.. - PRESSURE IN CRANK CASE
Ok, so might explain the weeps, lets check the PCV pipe work..
This is when it started to get smelly... i checked the oil separator to PCV hose, and found it bunged at the bottom end... nice.
Connected to the oil separator on the block.. a hose routed straight to atmosphere by the steering rack!!!
Ok, so ripped that all out.. checked all pipes very carefully for O ring damage or cracks and put it all back together... now I’m thinking, that’s the leak sorted!
Small vacuum in the filler cap, all looking good, except, now i have a rough idle... great
So started to do some fault finding, and the idle is rough, but improves if the sump oil separator hose is removed from the PCV and the PCV blanked, ok so air is getting into the crank case and then the intake unmetered..
Check idle and part throttle fuel adaptions and they are 5% and 15%, backs up the air leak.. reset them, and it struggles to even idle at all until it readjusts..
No fault codes other than an intake vane fault, probably just gummed up, its intermittent and i cant think of a relationship directly. Ill deal with that’s once i can keep oil in her!
So that’s pretty much where i am at. Run around for a day, and she isn’t smoking as much at stops, but there is still oil leaking..
If i rev the car, the smoke starts immediately, i was thinking this could be due to a leak only at high oil pressures, but I couldn’t rev it and look at the at the same time, and the air leak issue makes me think its a crankcase leak rather than a pressure side leak, but who knows right now..
the newly cleaned block and gear box shows the following -
Oil all over the driver side driveshaft - and this doesn’t help as this thrashes oil everywhere..
No leaks from cam cover.
No leaks from vacuum pump area
Oil drops on the back of the block, can pool around the underside of the head where it meets the block
Turbo feed and return lines all look pretty dry
Lower heater matrix pipe wet
CAT wet, this is where the smoke is obviously coming from
On the gearbox end of the block, just below the heater water take off pipe, there looks to be a repair or the block, around the core plug, but this looks dry
Oil over the block to gearbox area, but cant clearly see the route its coming down.
No clutch slip, although rear main seal is one thought..
Red shows where the oil residue is, Blue is where the block repair (JB weld or similar is, again, this appears dry.)
So, anyone got any thoughts?
Ive never known a head gasket to leak oil with no other symptoms, anyone else?
Anything else obvious I’m missing?
Any known issues here?
Does anyone have a 1.8TFSI block to show me where the oil galleys run compared to the repair on the end of the block?
I’m currently torn between engine out, or stacking up on oil and fitting a catch can to regain my idle!
Made a couple of posts, but I’m after some advice to lean on the experience here.
Firstly I’m a new member, so a bit of intro / background.
Just bought a A3 1.8TFSI S Line, to replace my Merc that someone decided to write off to save their brake wear...
Bought it cheap with a few obvious problems, which i hoped to pick through and give it a new lease of life... The exterior is in pretty good nick for the ages, as is the interior... its on 99,000miles
So i have ticked through the following little jobs -
Rear discs and pads
Repair the drivers interior door handle, spot of drilling and tapping
Front washer jets replaced as partially blocked, done, upgraded to fan type
Rear washer jets replaced as blocked
New wipers, just to cheer myself up one day
New battery in the remote - now she unlocks as well as locks! - the first help this forum provided
New front undertray
Now then.. the main event however - engine oil leak.
When i first purchased, this was pretty obvious, but i went ahead knowing that i could happily deal with most leaks, I’m an auto engineer by trade and have rebuild engines and done my own repair work for the past 20 years...
Perhaps i bit off more than i thought, as the first few days of ownership it was smoking at traffic lights etc.. i was nervously watching the oil level until the weekend..
So first up, the engine bay was drenched, looked like it had been leaking a while and covered most areas, so i spent a day going about some obvious easy wins, and then cleaned everything down so i could then later identify any further leaks.
Sump off, very clean indeed, pick up spotless, so resealed and refitted, starting to think someone’s been in here already..
Cam cover, i could believe that it had a weep, so popped that off and the cam chain cover vac pump etc.
This is where i found a missing rocker/follower!! (I popped a rushed thread up about this before!)
It had been spat out and was found in the well between 3 and 4 plug..
So a few days waiting for the TPS to get a new follower and hydraulic equaliser in, and i popped that all back together, resealed cover, new seal for cam chain cover, new vacuum pump seal, fuel pump follower inspected and all ok, cam chain tensioner was a letter revision and in good condition, chain stretch not severe..
All going well..
I noted that it had a new PCV valve a few months before buying, so double checked all was still ok with that - all working as it should be, nice taste of oil in the mouth, job done. Oil filler off..
HMMMM.. - PRESSURE IN CRANK CASE
Ok, so might explain the weeps, lets check the PCV pipe work..
This is when it started to get smelly... i checked the oil separator to PCV hose, and found it bunged at the bottom end... nice.
Connected to the oil separator on the block.. a hose routed straight to atmosphere by the steering rack!!!
Ok, so ripped that all out.. checked all pipes very carefully for O ring damage or cracks and put it all back together... now I’m thinking, that’s the leak sorted!
Small vacuum in the filler cap, all looking good, except, now i have a rough idle... great
So started to do some fault finding, and the idle is rough, but improves if the sump oil separator hose is removed from the PCV and the PCV blanked, ok so air is getting into the crank case and then the intake unmetered..
Check idle and part throttle fuel adaptions and they are 5% and 15%, backs up the air leak.. reset them, and it struggles to even idle at all until it readjusts..
No fault codes other than an intake vane fault, probably just gummed up, its intermittent and i cant think of a relationship directly. Ill deal with that’s once i can keep oil in her!
So that’s pretty much where i am at. Run around for a day, and she isn’t smoking as much at stops, but there is still oil leaking..
If i rev the car, the smoke starts immediately, i was thinking this could be due to a leak only at high oil pressures, but I couldn’t rev it and look at the at the same time, and the air leak issue makes me think its a crankcase leak rather than a pressure side leak, but who knows right now..
the newly cleaned block and gear box shows the following -
Oil all over the driver side driveshaft - and this doesn’t help as this thrashes oil everywhere..
No leaks from cam cover.
No leaks from vacuum pump area
Oil drops on the back of the block, can pool around the underside of the head where it meets the block
Turbo feed and return lines all look pretty dry
Lower heater matrix pipe wet
CAT wet, this is where the smoke is obviously coming from
On the gearbox end of the block, just below the heater water take off pipe, there looks to be a repair or the block, around the core plug, but this looks dry
Oil over the block to gearbox area, but cant clearly see the route its coming down.
No clutch slip, although rear main seal is one thought..
Red shows where the oil residue is, Blue is where the block repair (JB weld or similar is, again, this appears dry.)
So, anyone got any thoughts?
Ive never known a head gasket to leak oil with no other symptoms, anyone else?
Anything else obvious I’m missing?
Any known issues here?
Does anyone have a 1.8TFSI block to show me where the oil galleys run compared to the repair on the end of the block?
I’m currently torn between engine out, or stacking up on oil and fitting a catch can to regain my idle!
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