Audi S3 8L (2003)
Discussion
Hi guys.
I have recently bought an Audi S3 8L off a friend who hadn't used the car in over a year and provided me with a list of things that needed doing, a bit of TLC.
I put it into the garage and gave them the list and to be honest, I don't believe they done much to it. Once getting it on the road there was a knocking sound on the front left wheel which I have been advised it was the CV joint. Having ordered a new driveshaft I couldn't get the garage to book me back in and since the knocking has stopped. I suppose at the moment it's out of sight out of mind.
Since driving it I have always found myself thinking it's not as fast as I thought it would be but didn't know too much as I have never driven an S3 before. Having put the car in for some bodywork touch-ups the owner confirmed that it was lacking power. When accelerating fast there is a type of whistling noise like there could be a leak from somewhere in the boost pipe system. (unexperienced me thought it was the dump valve) I ordered new upper boost pipes and got a friend with mechanical experience to help fit them. Taking off the old boost pipes we noticed A) there were no cracks in the pipes B) oil inside them. My friend suggested the turbo could be leaking but wasn't 100%. Checking the oil it was on the lower side, despite having an apparent full service and MOT in November.
I took the car for a test drive once fitted and give it a bit of a booting, it definitely sounded better and felt slightly faster however the whistling noise under acceleration was still present. Once I returned I opened the bonnet to hear the alloy pipe coming from the turbo quite literally bubbling like it was boiling the oil inside it.
It would be much appreciated if someone could shed some light on this for me?

I have recently bought an Audi S3 8L off a friend who hadn't used the car in over a year and provided me with a list of things that needed doing, a bit of TLC.
I put it into the garage and gave them the list and to be honest, I don't believe they done much to it. Once getting it on the road there was a knocking sound on the front left wheel which I have been advised it was the CV joint. Having ordered a new driveshaft I couldn't get the garage to book me back in and since the knocking has stopped. I suppose at the moment it's out of sight out of mind.
Since driving it I have always found myself thinking it's not as fast as I thought it would be but didn't know too much as I have never driven an S3 before. Having put the car in for some bodywork touch-ups the owner confirmed that it was lacking power. When accelerating fast there is a type of whistling noise like there could be a leak from somewhere in the boost pipe system. (unexperienced me thought it was the dump valve) I ordered new upper boost pipes and got a friend with mechanical experience to help fit them. Taking off the old boost pipes we noticed A) there were no cracks in the pipes B) oil inside them. My friend suggested the turbo could be leaking but wasn't 100%. Checking the oil it was on the lower side, despite having an apparent full service and MOT in November.
I took the car for a test drive once fitted and give it a bit of a booting, it definitely sounded better and felt slightly faster however the whistling noise under acceleration was still present. Once I returned I opened the bonnet to hear the alloy pipe coming from the turbo quite literally bubbling like it was boiling the oil inside it.
It would be much appreciated if someone could shed some light on this for me?
I’m going to point you straight to AudiSport.net. There’s a specific 8L section. But from what I remember....
I would start with dropping the sump, changing the pick up pipe then making your way from there. The engine breathes into the intake so there will always be some oil in there. So take off all the boost pipe work. Clean it all out including the two intercoolers. Put back together and do a pressure test. I made a home made kit that was cheap to do.
Then move on to replacing all vacuum pipe for the N75. It’s the 4mm id stuff.
Then move on to the PCV. I would vent to a catch can. Fit a new 710N DV. It’s the best one for the car. That’s just the boost stuff!
It will be worth it. I think the 8L is the best looking S3. I had an 8P and it needed a good 1.5k spending on it just to get it up to a good mechanical standard.
I would start with dropping the sump, changing the pick up pipe then making your way from there. The engine breathes into the intake so there will always be some oil in there. So take off all the boost pipe work. Clean it all out including the two intercoolers. Put back together and do a pressure test. I made a home made kit that was cheap to do.
Then move on to replacing all vacuum pipe for the N75. It’s the 4mm id stuff.
Then move on to the PCV. I would vent to a catch can. Fit a new 710N DV. It’s the best one for the car. That’s just the boost stuff!
It will be worth it. I think the 8L is the best looking S3. I had an 8P and it needed a good 1.5k spending on it just to get it up to a good mechanical standard.
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