2.7Lturbo

no


just



no



do it right the first time get the tool

audiworldzane

Thanks for the additional information. I figured it out as I went, but didn't realize the wing pieces are keyed to the cam. That gives me a lot more confidence in the design. Otherwise, you would have no control over the cam alignment once the pulleys come off.

I chose not to remove the pulleys and just use the winged pieces and the alignment tool T40005 to get the cams in the right spot before installing the new belt. I also used the crankshaft locking pin. Initially, I didn't want to purchase the extra tools, but I am really glad I did because my car starts and runs great.

I had alot of concern about the eccentric cam because as you described it affects the timing. (I didn't fully understand the affect until I got it back together and discussed it with my fellow engineer, then I read your comment and it was confirmed.) I didn't have the tool used to torque it into place, so this is probably an area that is not perfect on my replacement. It also doesn't seem like the most precise method to tell the mechanic to line it up with the pulley on the waterpump. Regardless, my belt was really loose on both sides when I removed it. After, it was very tight.

Is there an adjustment period for the ECU to adapt to the new belt or is it set where it's set? It seemed like the MPG gauge was lower after the change, but that was the only noticable change.

All in all I am glad I did the change myself, but I had several doubts throughout the process particularly with the oil cooler that made me question the attempt. I had trouble with the front and rear bolts on the top of the cooler. I stripped both hexes on these bolts (call it OE if you want but those things were welded in there) but I was able to get them out by praying. Anyway, I did raise and lower the engine off the mounts in order to remove the cooler. I don't see how this procedure is possible without this step since the cooler is part of the mount. Anyway, I would be glad to answer questions about the process if anyone wants amateur advice. I am just thankful I survived and the car runs so well.


The good! My 4.2L A6 reassembled and running


The bad. The plastic coolant pipe... in three pieces.


The ugly! Stripped bolts from the front and rear of the oil cooler housing


The engine with cooler removed. Looks like loads of room...right.


Oil cooler off

NJA642

Certainly a confidence-inspiring project when you are finished & everything works. Normal to get antsy when everything is apart, especially if it is your daily driver.

Other folks can correct, but I don't think the ECU does much in the way of 'learning'; it should be working ignition timing to maximize fuel burn based on feedback from the 02 sensors. Keep an eye on your mileage, there might be something else going on.

Since you have the 4.2L, you might want to check the variable length intake runner mechanism (front of the intake manifold has two vacuum bellows that rotate shafts inside the manifold that change the route air takes depending on engine RPM) They can get 'stuck', the little plastic links can break, etc. Car off the springs should pull the bellows into the extended position, when you start the engine I think both should close once the engine warms up, RPM settles down & engine goes into closed loop. (vacuum is applied or removed from the bellows by two small electronic valves controlled by the ECU) If this isn't working correctly, you could be running at slightly lower power/efficiency.

SloopJohnB@mac.com

I did my 2K4.2 oil cooler pipe w/o jacking up the engine...simply remove the bracket and lower engine mount.

Your oil cooler looks somewhat different than mine; I don't recall removing the oil filter housing/mount.

gofish

I have a similar story with a different twist/challenge. My car is a 2006 A8l D3 4.2L 134,000 mileage. I went through the (not so wise) attempt at doing the timing belt without the proper timing tools method and the cam snapped back roughly 20 25 degrees. I freaked out for a moment pulled myself together and did the right thing...got the tools necessary for the job. Now( As the great Paul Harvey used to say) the rest of the story..) I discovered that the chain gear on the end of the cam intake side was missing two teeth and the approaching teeth to the two that were broken were starting to wear and bend towards the two broken teeth. QUESTION, Is it possible that the chain tensioner could have malfunctioned causing the chain to be loose enough to damage the gear? Is there a way to possibly test the chain tensioner? And lastly does anyone have any ideas of what else could have caused the damage? By the way the car ran great prior to this maintenance "attempt". Any ideas or criticisms will be very much appreciated.

audiworldzane

I am probably not the best one to ask about this repair. I did my timing belt with the tool as described in this thread. The car ran great for 2 years then the cam chain tensioner failed on the passenger's side intake. The tensioner has plastic shoes that got chewed up. I don't think any of the teeth on my sprockets got damaged.

My experience with this was that the chain and sprocket won when the tensioner messed up and got stuck between meaning the plastic just came apart. But there might be a different failure scenario that could cause the damage to the sprocket. I opted to get rid of the vehicle rather than replace the intake manifold because I don't have a garage to work on it and I needed transportation sooner than I could get to it. I don't think this helps you much, but I did watch videos on youtube for replacing the tensioner that seemed pretty straight forward. This required the removal of the cam shaft which would allow you to replace the sprocket. You still have to reset the timing correctly. In my case, I suspected my valves were damaged and possibly the pistons, so I would have needed to overhaul that side of the block. I gave up. Hope you can fix yours.

pswq

Did the cam belt, water pump, thermostat, belt tensioner, and that cursed oil cooler pipe about 6 months ago. I did get the cam alignment tool and crank locking pin. The oil cooler pipe was a complete pain but it can be done without engine removal - I only took off the RH engine mount. I also had to use small lights, a mirror, and a cut down hex key to get to that really difficult-to-get-to hex. The biggest risk is rounding it out - if that happens you are stuffed.
For the cam belt, etc., using Elsawin and a couple of online sources it all went fairly easily. When removing the front panel some of the bolts on the RH side of a RHD car cannot be reached from below, but access is possible from above.
I've just changed the transmission filter and fluid - at 163000 kms it seemed a good move. As you might expect the fluid was dark and there was a thin layer of fine sludge in the pan. Not sure if it was needed, but happier that I know what's in there.

kylemc001

Reviving this old thread.

I am working on my 2000 4.2 A6. Long story short timing was off bad and have a bunch of bent valves. I haven't seen any timing marks for crankshaft. I have the locking pin but can't seem to find the correct TDC to get it in. Is there a way I can do this with the cylinders since the cams are off? Im not sure whether cylinder 1 or 3 should be at TDC when crank is lined up. Thanks all.

audiworldzane

I no longer have my Audi, so I can't verify this, but I remember a mark on the crank shaft pulley that lined up with an associated mark on the lower cover. When these marks lined up and the tool that spans the two pulleys lined up it was at TDC. I think if the tool was aligned correctly but the lower mark was not, it was 180 deg out. I am not sure about cylinder firing order, but this should be easy to find on the internet.

Just FYI. My timing got off as well, and that is why I parted ways. Mine didn't have anything to do with the belt. It was the internal cam tensioner that failed and allowed the cam chain to skip teeth. I didn't try to fix, because I didn't have the money to risk failure of installing new heads. I hope you find success in your endeavor.

the_duke

There should be a notch on the harmonic balancer that lines up with a mark on the plastic cover.

Looks similar to this: