As some of you know, I had the EPC light and fault - Supercharger magnetic clutch stuck open. On my FIS Control I could see the boost built quickly to over 1 bar, like normal, then it would drop right back to less that 0.5 bar, then the EPC light came on and boost dropped altogether and it went into limp mode. My S5 has done 55k miles and has been stage 2 (just crank pulley (187mm) for 3.5 years and 15k miles. No unusual noise, except the metallic clank when activated by vcds.
I rang a few Audi Indy's, but either they didn't get back to me or 1 of them said I would need to take it to the dealer as it needs a special tool. Why an Audi specialist would turn down work because they need a special tool, kind of sums up how specialist they are. Well that didn't give me any confidence to go anywhere near a garage, like I haven't done before, purely because I don't have the trust. This just adds to my doubts!
Anyway, decided to do it myself, replace the SC clutch, change the SC oil, change the PCV solenoid valve (was getting intermittent PCV malfunction fault, but no issues) and check over the bits under the Supercharger.
Firstly, I must say, I was anxious about removing the supercharger, but it was dead easy!! Took me 40 mins!! First time and reading the Audi workshop manual! I rekon doing it again, 20 mins tops! Most of the time is driving up the ramps, removing the undertray and disconnecting the coolant pipes for the SC!
The special tool is the VAS 6909, this is a long lead that connects to the battery posts and has a switch on it for energizing the clutch when installing. This is around £140!! So you know me, I made my own! Part of my battery charger with clips, then some wire with a lamp switch and small female spade connectors! Cost, a few quid for the bit of wire and a set of electrical connectors! What I also needed to check is which pin on the clutch was positive. I've read polarity is anyway on magnetic clutches, but also read, some have a resistor that can blow! Didn't want to blow my brand new £500 clutch!! So with VCDS you can run the activation of the clutch, but it is a pulse, so couldn't use it for installation. Just read the output at the connector on the car to find the + and -.
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I tested the 'special tool' on the old clutch before using it on the new clutch.
Then I followed the workshop manual to remove the supercharger. Marked all 4 of the vacuum pipes and connectors. I was genuinely surprised when removing the SC that, that was all it was! Well I had a bit of help from a crappy Audi Technician, that messed my car up with the fuel rail recall, he had also broken the clip for the fuel charcoal pipe and the bracket on the rear wiring harness that is supposed to attach to the SC.
Luckily these haven't caused any issues!
It is quite a heavy beast the SC. I had to kneel on the slam panel to lift it out.
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You can see a bit of historical coolant leak between the stat and behind the pump. Didn't see any other signs of leaks etc. The pump had a very slight bit of play, but not enough to cause concern or to change it.
Now I have removed the SC, I would do it again!
Also to note as the CREC engine has port injection, the intake valves and ports looked brand new! No carbon! Could also be that I exclusively use Shell V power with a bit of Momentum 99 every now and then. I did try and take a pic, but it wouldn't focus because the tumble flaps where in the way. I have seen then manually being pushed open, but I didn't want to break anything just to take a pic!
Now removing the clutch! It does say in the manual to use another special tool, a puller to remove the clutch plate as this is clamped onto the input shaft, but it just pulled off by hand.
A few pics of the new and original clutch. Note the hot blue spots!! This clutch was seriously slipping. you can see a lot of wear! I'm not sure if I could have moved the clutch plate on the input shaft towards the magnet side as I guess the gap would be more than when new, so may be the magnet was struggling pulling against the plate springs, so this was causing the slippage?
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I have also put another access hole in the top of the clutch so if needed I can adjust without removing anything! It would have been good to test adjusting the old clutch, but I didn't have the time as it could have been a weak magnet too through age and wear.
Also the old clutch can be repurposed as a welded clutch for those running Stage 2 +/3!
Here is the old oil out of the Supercharger in the beaker, with the new oil in the fill tube on the left. My god the old oil it stinks! Like a vinegary nasty smell.
The new oil is from Westway oils and is a supercharger/turbine specific oil with military spec. It is equivalent or exceeds AC Delco/GM supercharger oils which are equivalent to Audi's oil which is also £50! I paid £15!
![Image]()
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I only got about 120ml of oil out, but to test, I put 50ml of new oil in, used a drill to spin the SC and flush the new oil around and then drained and got 50ml exactly back out, so I suspect that is all that is in the SC. You have to hold the SC up and rotate it round to get the last bits out. This TVS1320 charger should take 152ml, so I put 140ml back in thinking there was still a bit left inside. you shouldn't overfill chargers as they can blow seals as they are a sealed unit. Some come with pressure relief valves.
Fitting new clutch with my special tool.
![Image]()
The clutch plate is tighten through an access hole in the cover from the bottom. But I thought to put another hole in the top for future adjustments. Just wish I had tested the old clutch with adjustment on the input shaft just out of curiosity!
Put it all back together and refilled supercharger coolant system (mine is divorced so no messing with the main engine cooling system. Refilled with DEI Chill charger and 25% anti freeze mix. After a drive the pipes were cold, including the intercooler bleeds are the rear and the SC was hot, so the charge cooling is doing its job well!
Went for a drive to test and the full power was back, 80mph, 4th gear = a bit of wheel slip again, in the rain!
If anyone wants their SC clutch doing, let me know! quite an easy job! I'm glad I did this job myself and it was straight forward to do!
Or if anyone wants a welded supercharger clutch, let me know, I'll do them on an exchange basis!
Edit, Last procedure is to reset the clutch adaptations with VCDS.
I rang a few Audi Indy's, but either they didn't get back to me or 1 of them said I would need to take it to the dealer as it needs a special tool. Why an Audi specialist would turn down work because they need a special tool, kind of sums up how specialist they are. Well that didn't give me any confidence to go anywhere near a garage, like I haven't done before, purely because I don't have the trust. This just adds to my doubts!
Anyway, decided to do it myself, replace the SC clutch, change the SC oil, change the PCV solenoid valve (was getting intermittent PCV malfunction fault, but no issues) and check over the bits under the Supercharger.
Firstly, I must say, I was anxious about removing the supercharger, but it was dead easy!! Took me 40 mins!! First time and reading the Audi workshop manual! I rekon doing it again, 20 mins tops! Most of the time is driving up the ramps, removing the undertray and disconnecting the coolant pipes for the SC!
The special tool is the VAS 6909, this is a long lead that connects to the battery posts and has a switch on it for energizing the clutch when installing. This is around £140!! So you know me, I made my own! Part of my battery charger with clips, then some wire with a lamp switch and small female spade connectors! Cost, a few quid for the bit of wire and a set of electrical connectors! What I also needed to check is which pin on the clutch was positive. I've read polarity is anyway on magnetic clutches, but also read, some have a resistor that can blow! Didn't want to blow my brand new £500 clutch!! So with VCDS you can run the activation of the clutch, but it is a pulse, so couldn't use it for installation. Just read the output at the connector on the car to find the + and -.
I tested the 'special tool' on the old clutch before using it on the new clutch.
Then I followed the workshop manual to remove the supercharger. Marked all 4 of the vacuum pipes and connectors. I was genuinely surprised when removing the SC that, that was all it was! Well I had a bit of help from a crappy Audi Technician, that messed my car up with the fuel rail recall, he had also broken the clip for the fuel charcoal pipe and the bracket on the rear wiring harness that is supposed to attach to the SC.
Luckily these haven't caused any issues!It is quite a heavy beast the SC. I had to kneel on the slam panel to lift it out.
You can see a bit of historical coolant leak between the stat and behind the pump. Didn't see any other signs of leaks etc. The pump had a very slight bit of play, but not enough to cause concern or to change it.
Now I have removed the SC, I would do it again!
Also to note as the CREC engine has port injection, the intake valves and ports looked brand new! No carbon! Could also be that I exclusively use Shell V power with a bit of Momentum 99 every now and then. I did try and take a pic, but it wouldn't focus because the tumble flaps where in the way. I have seen then manually being pushed open, but I didn't want to break anything just to take a pic!
Now removing the clutch! It does say in the manual to use another special tool, a puller to remove the clutch plate as this is clamped onto the input shaft, but it just pulled off by hand.
A few pics of the new and original clutch. Note the hot blue spots!! This clutch was seriously slipping. you can see a lot of wear! I'm not sure if I could have moved the clutch plate on the input shaft towards the magnet side as I guess the gap would be more than when new, so may be the magnet was struggling pulling against the plate springs, so this was causing the slippage?
I have also put another access hole in the top of the clutch so if needed I can adjust without removing anything! It would have been good to test adjusting the old clutch, but I didn't have the time as it could have been a weak magnet too through age and wear.
Also the old clutch can be repurposed as a welded clutch for those running Stage 2 +/3!
Here is the old oil out of the Supercharger in the beaker, with the new oil in the fill tube on the left. My god the old oil it stinks! Like a vinegary nasty smell.
The new oil is from Westway oils and is a supercharger/turbine specific oil with military spec. It is equivalent or exceeds AC Delco/GM supercharger oils which are equivalent to Audi's oil which is also £50! I paid £15!
I only got about 120ml of oil out, but to test, I put 50ml of new oil in, used a drill to spin the SC and flush the new oil around and then drained and got 50ml exactly back out, so I suspect that is all that is in the SC. You have to hold the SC up and rotate it round to get the last bits out. This TVS1320 charger should take 152ml, so I put 140ml back in thinking there was still a bit left inside. you shouldn't overfill chargers as they can blow seals as they are a sealed unit. Some come with pressure relief valves.
Fitting new clutch with my special tool.
The clutch plate is tighten through an access hole in the cover from the bottom. But I thought to put another hole in the top for future adjustments. Just wish I had tested the old clutch with adjustment on the input shaft just out of curiosity!
Put it all back together and refilled supercharger coolant system (mine is divorced so no messing with the main engine cooling system. Refilled with DEI Chill charger and 25% anti freeze mix. After a drive the pipes were cold, including the intercooler bleeds are the rear and the SC was hot, so the charge cooling is doing its job well!
Went for a drive to test and the full power was back, 80mph, 4th gear = a bit of wheel slip again, in the rain!
If anyone wants their SC clutch doing, let me know! quite an easy job! I'm glad I did this job myself and it was straight forward to do!
Or if anyone wants a welded supercharger clutch, let me know, I'll do them on an exchange basis!
Edit, Last procedure is to reset the clutch adaptations with VCDS.
