DIY - A6 3.2 Upper Timing Chain Tensioner Replacement
 

Okay, here it is. After getting the run around from the "Audi Specialists" in my area, I decided to just do it myself. I've tried my best to outline the entire procedure to change the timing chain tensioners on the Audi 3.2 Liter engine. If you hear a loud clicking noise from the rear upper area of the engine, this is apparently a common problem and the upper tensioners are most likely the culprit. There is another lower hydraulic tensioner, if that has failed then you're out of luck and have to pull the engine. This procedure is not hard, just be careful, be patient, and take your time. Most importantly, you do NOT have to pull the engine out to do it. Someone with average mechanical skill should be able to knock this out in a couple hours. Good luck!

Audi 3.2 FSI Upper Timing Chain Tensioner Replacement

Parts

Warning - Please fight the urge to pull the retaining pins when you get the part. The seals inside can be damaged trying to recompress them and they must be compressed to install. The rear photo shows the dark backing plate, they're held only loosely with metal tabs. Be carefull when installing that they do not become misaligned.

1. Timing chain tensioner, left upper - Part Number: 18266-01183647 (Partsgeek.com) $219.17
http://s17.postimg.org/vut16qoan/left.jpg
2. Timing chain tensioner, right upper - Part Number: 18264-01183648 (Partsgeek.com) $191.99
http://s30.postimg.org/e4r0j8njl/right.jpg
3. RTV Silicone

Tools Needed

1. T40058 – Crankshaft Turning Socket - ebay $19
http://s29.postimg.org/kq5454i7b/t40058.jpg
2. T40070 – Camshaft Locking Tools - ebay - Audi timing tool set $158 (el paso tools store - made by baumtools)
http://s28.postimg.org/7lxpmxue5/t40070.jpghttp://s9.postimg.org/ynplgyim7/tools.jpg
3. T10035 – Multi-point Socket (12 Point 14mm Socket) - Included in timing toolset
http://s28.postimg.org/uv6j2xue5/T10035.jpg
4. T-30 Torx Bit (6mm)
5. 3/8 Stubby Swivel Ratchet - Harbor Freight $9.99 - Bottom torx bolts on cam covers are a bitch and tough to get to, this tool and a 1" extension are life savers! DO NOT STRIP THOSE TORX BOLTS!
http://s11.postimg.org/tdc1g3hg3/swivel.jpg
6. ½ Extendable Ratchet - Harbor Freight $16
7. Torque wrench
8. Metric Sockets
9. Ratchet extensions

Installation Procedure


1. Remove air filter plenum and upper filter housing ( You can leave back part mounted to inner fender)
2. Remove radiator coolant reservoir
3. Disconnect spark plug harness on both sides
4. Mark and remove any sensors that may restrain the spark plug harness so it can be moved clear of the valve covers
5. Carefully pop out all 6 individual ignition coils from the spark plugs
6. Use T-30 torx bit to undo all valve cover bolts for each side
7. Remove right and left valve covers
8. Use T-30 torx bit and stubby ratchet to undo all rear timing chain cover bolts on each side (Be careful, they can be tough DO NOT STRIP!)
http://s10.postimg.org/nea71t9ah/cam_cover.jpg
9. Use T40058 Crankshaft tool on ½ Drive extended ratchet to manually turn engine clockwise until the threaded holes on the end of the camshafts (firewall side) face upward on each cylinder bank.
http://s14.postimg.org/8c66ygczl/crank.jpg
http://s3.postimg.org/3kgb8i2ur/holes.jpg

10. Bolt on T40070 locking tools on each cylinder bank. Make sure the holes are aligned upright and the bolts screw in smoothly. If needed rock crankshaft with back and forth till it’s perfectly aligned. You don’t want to try bolting it on unaligned or you can break bolt on the camshaft. Then you have to MIG weld a nut on it to extract (Don’t ask how I know this)
http://s15.postimg.org/u9iq0u5mz/locked.jpg

11. With both camshafts locked, you can now remove the cam adjusters bolted to the end of the camshafts.
12. Use T10035 Socket and loosen the 12-point bolts on each of the camshafts on the right cylinder bank.
http://s17.postimg.org/unxxgv8n3/cam1.jpg

13. Carefully wiggle the cam adjusters off the end of each camshaft. Start with the intake and when it’s off just rest the chain on the cylinder head casting directly behind the cam adjuster. Do the same for the exhaust camshaft. Mark each cam adjuster as intake or exhaust (the exhaust cam adjuster has a metal spring/clip on it, the intake doesn’t) Don’t worry if the chain moves, the engine is locked in place. Just Don't touch the crankshaft while the engine is locked.
14. Take the new right tensioner out of the package and note the location of the mounting holes, you will be undoing these on the old tensioner in the engine.
http://s28.postimg.org/j57atj3ml/bolts.jpg
15. Stuff some shop rags or paper towels down the galley were the timing chain comes up from, this is so you don’t accidentally drop any of the tensioner mounting bolts down into the rear of the engine. That would be a world of hurt.
16. Undo all the mounting bolts (T-30 torx) and carefully wiggle the tensioner up and out of the rear of the engine. The hydraulic piston in the tensioner may drop out just be careful when removing. My old one was completely compressed and stuck down.
17. Carefully place new tensioner into position, you may have to move the chain around to get it into place. BE CAREFULL THE BACKING PLATE ON THE NEW TENSIONER STAYS ON AND DOESN’T SHIFT. DO NOT REMOVE THE RETAINING PIN (T40071)ON THE NEW TENSIONER YET!
18. Reinstall all of the chain tensioner mounting bolts. I started with the top/easiest one then wiggled it around till I could get a second bolt in making sure it’s aligned. Then I installed and tightened the remaining bolts.
19. Reinstall the cam adjusters, start with the exhaust, pull the timing chain out slightly and place it around the cam adjuster. Then gently wiggle adjuster back onto the camshaft. Do the same for the intake cam adjuster. You may have to play with it a little, be patient and careful and make sure both adjusters are on straight. UPDATE - I've been asked several times about do the cam adjusters need to be aligned in a specific position when reinstalling. They are not notched or indexed in any way. The factory manual makes no mention of installing them in any spefici aligned position so it appears it doesn't matter. Just make sure they're on!
20. Now, you may now pull out the tensioner retaining pin. The piston should pop out and tension the chain.
21. If the retaining clip pops out before you get the cam adjusters back on, you must remove the tensioner from the engine and manually squeeze the guide rail till it’s completely compressed. Then, while holding it, you can put the retaining pin back on it. There is a ratchet mechanism inside the tensioner piston that will not release until it’s compressed fully. Be careful, you can damage the seals inside if you try forcing it. I think this is the reason these tensioners fail again prematurely, so be careful!
http://s30.postimg.org/731kvgz0h/tensioner2.jpg
22. Reinstall the camshaft adjuster retaining bolts. First torque them to 30 lb/ft, then60 lb/ft, then tighten them another ¼ turn.
23. Repeat this procedure for the left cylinder bank
24. Clean old sealant from rear camshaft covers and apply new RTV silicone
25. Reinstall the rear camshaft covers
26. Reinstall valve covers
27. Reinstall coils, wiring harness, etc.
28. Reinstall intake and coolant reservoir
29. Make sure crankshaft turning tool has been removed
30. Double check everything is back in place and fire up the engine!

My engine fired right up, problem resolved, and I saved thousands. Every European specialist shop I called in Tampa Bay either didn't have the timing tools or refused to do the tensioners without pulling the engine. I've seen timing chains last 300k+ miles on many vehicles, they are designed to last the life of the vehicle. If your shop tells you you MUST pull the engine because of chain stretch or broken guides, ask them whats more likely to fail, a hardened alloy chain or a plastic hydraulic piston seal. That's the purpose of tensioners, to compensate for chain stretch (to a point of course). Yeah, okay, sure it can't be done.

That's a great post!!!! too bad I have a 4.2 :(

Great write-up and post. Hopefully, I won't need to do this repair on my '06 A6 Avant. But if I do, I have your write-up saved in my files. Thanks.

Fabulous Writeup!
 

Thanks for taking the time to photo and write it up!
I was just looking at the upper chain covers last week, thinking that this should well be possible without removing the engine, and you just proved it.
Did you use the blue handled tool from the set to hold the cam adjuster in place while undoing the T10035 bolt?
The 'cam aligners' that screw in from the top are great holders, but don't really look designed to hold against the 60 ft-lb.
how easy was it to clean up the RTV from the back of the head without getting crumbly bits down into the engine?
If you have photos (both front and back side please) of your old guides, I would be interested to see the wear patterns. How many miles again on the old ones?
superb job!

Hi, well the shop manual shows using them and it also specifies to install the crankshaft locking pin which is utterly impossible with the engine still in the car. I considered it but I ended up having no trouble installing and removing the cam adjusters with just the camshaft locks in place on both banks. The flat mating surfaces on the locks and cam when bolted together stop any kind of movement whatsoever and did not appear to put any undo strain on the assembly. Cleaning the cover mating surface was no problem, there's sufficient room. I'll see if I can get pictures of the old tensioners but honestly, they showed very little signs of abrasion or wear. I just bought the car about 2 months ago with 100k miles on it. I have no clue if these are the original tensioners or not but the engine appears to have been untouched (or at least properly reassembled) when I got into it.

Hi,

one of the best posts on this forum. Think I may be going down the same road. What were your symptoms? Or, did you just do this as preventive maintenance?

symptoms
 

My 05 A6 3.2 just started acting up.. Loud diesel sound. How long before i need to change the tensioner?

My check engine light came on and gave me enough warning to get the car to the dealer. Since I was already aware of the issue I went straight to the dealer and put less than 20 miles on the car once the light came on.

Hi,

Your description says that you do not need to take the engine out. Yet the one photo you show is with the engine out. Did you remove the engine?

Hi, great instructions thanks. I had loud clatter and desiling sound from the driver side bank. After watching a few videos and reading this fourm decided to replace the driver side tensioner. But looking at it it seems like the Spain is tight and when I push on it, has very little movement. Kinda stumped now. Any help? Thanks.