07 - S6 Coolant in oil - Complete Engine Teardown

A6 All/ S6 All
#81

I have not been taking many pictures lately as I have just been cleaning and re-assembling the original components that were removed six months ago. With all the hoses and wiring on these engines, I have spent a fair bit of time going over the pictures I took last October to make sure things are going back on in the reverse order that I took them off. Logically, you just work from the bottom of the engine up. (ie. a/c compressor, power steering pump, starter, engine mounts, manifolds, coolant pipes)

Here is the power steering pump and associated fasteners

http://audirevolution.net/addons/albums/images/428384036.jpg

The only thing I replaced as far as the power steering pump was concerned were the two metal gaskets that seal the banjo bolt connection to the pressure line. I removed the pressure line so I could confirm that the pump was full of fluid (before reinstalling) by pouring oil into the suction line and manually turning the pump until oil came out the discharge side. The splines on the drive shaft were coated with spline grease and the pump was re-installed.

Here is a shot of the starter installed with the after run coolant pump. The electrical connection to the starter and alternator was also installed at this time as it is much easier to do before the exhaust manifolds are put on.

http://audirevolution.net/addons/albums/images/801038526.jpg

Here is a shot of the coils and plugs.

http://audirevolution.net/addons/albums/images/982008148.jpg

I went with a one step colder plug to go along with the JHM tune/exhaust and my plans to drive it hard once I get it back on the road. If I get any fowling, I still have my stock NGKs, which are less than two years old, that I can through back in. The coils were all replaced less than two years ago so I did not see a need to replace them.

Here is a shot of the manifold gaskets along with the copper plated nuts and the Audi ā€œhot boltā€ paste which looks like some form of copper based anti-seize.

http://audirevolution.net/addons/albums/images/142838811.jpg

When I was removing the exhaust tracts last October, half a dozen of the studs came out the heads as the nuts were seized in place. The studs in the heads are available as a separate part.

http://audirevolution.net/addons/albums/images/219099795.jpg

Unfortunately , the studs in the ends of the exhaust tracts are not. When I replaced one of my y-pipes last summer, two of the nuts were so seized, they just rounded right off when I put the socket to them. I ended up cutting half the nut off with a die grinder and then knocking the rest off with an air chisel. In the process, I gouged out a few chunks with the die grinder so I replaced the three studs with pieces of stainless steel threaded rod.

http://audirevolution.net/addons/albums/images/483657221.jpg

Prior to installation, a thread chaser was run through all eight O2 sensor ports and a die was run across all of the studs

Here is a current shot of the engine with the manifold tracts installed.

http://audirevolution.net/addons/albums/images/775116584.jpg

With the exhaust installed, it is time to move onto the cooling system.

I believe I counted twenty six different coolant hoses in the engine compartment.

Here are the parts diagrams for the FEED and RETURN sections of our cooling systems.

http://audirevolution.net/addons/albums/images/11875652.jpg

Some of them are ridiculously expensive so I decided to only replace the ones that either needed to be replaced or were completely in accessible (or require a fair amount of disassembly work) with the engine in the vehicle.

I will leave it at that for now as I am currently waiting on some of the hoses I ordered to arrive.

#82

^^A picture of beauty.

#83

I figured it was time to update this thread as I hope to get the engine back in the vehicle this weekend.

I replaced the following hoses:

The two short hoses and the cap on the rear of the engine.

http://www.audirevolution.net/addons/albums/images/397497587.jpg

I also replaced both hoses on each of the oil cooler,

http://www.audirevolution.net/addons/albums/images/722223714.jpg

and the alternator

http://www.audirevolution.net/addons/albums/images/323900179.jpg

With all of the plumbing done, it was time to move onto the electrical.

This started with the installation of eight new O2 sensors. I went with Bosch ones from Rockauto because they were inexpensive and their shipping costs to Canada were reasonable. Here they are installed with the Bosch p/ns given.

http://www.audirevolution.net/addons/albums/images/571665388.jpg

All of the upstream sensors are direct fit with the appropriate length harness and properly keyed connectors.

The four downstream ones (Bosch p/n 16136)are a little more generic with much longer harnesses and non-keyed connectors. Bosch includes the mating half of the connector with each sensor. Only one of the four had to be changed. The picture below shows the difference between the factory and the Bosch replacement connectors (harness side).

http://audirevolution.net/addons/albums/images/63263578.jpg

I could have taken the original factory connector off of the old sensor and transferred it to the new sensor but it has been my experience on older electrical connectors that it is much easier to remove the female sockets out of a connector than it is to remove the male pins.

Next up was the installation of the harness itself.

http://audirevolution.net/addons/albums/images/804089730.jpg

I went through all of the connectors and only found one that the latch on the housing was damaged on so I replaced it. I had previously replaced both throttle body and the two fuel pump connector housings as they were being held on with zip ties.

The arrangement is a little convoluted back by the O2 sensor connectors on the transmission. This is where it is key to take good before pictures so you can get all the clips and zip ties installed where they belong You can see where I had to coil up the excess harness lengths on the Bosch downstream sensors.

http://www.audirevolution.net/addons/albums/images/238127332.jpg

Also, if you plan on doing this, install the transmission control portion of the harness (with the heat shields) BEFORE you install the exhaust. It is doable with the exhaust in place but much more of a PITA.

Here is a shot of how things are looking now. I suspended the engine and tranny between one of the legs on the car lift and the engine crane. It makes it a lot easier to get some of the return hoses and piping installed when you have full access to the underside. It also makes it easier to get the subframe back in place and everything positioned correctly on the motorcycle lift to install back in the vehicle.

http://audirevolution.net/addons/albums/images/893106434.jpg

That is it for now. Next I have to winch the car back into the garage and get it on the lift so I can do some work in the engine bay.

#84

Did you consider eliminating the Cats and going straight piped?

#85

I thought very briefly about punching them out but my goal with this engine drop was to resolve an internal coolant leak and hopefully resolve a few other minor annoyances.

I did not want to introduce any other changes to the system at this time which may impact how the engine runs.

If I am satisfied with how it runs over the next six months, I may drop it again in the fall and either go with headers or FI.

#86

drop in 6 months? Damn you are ballsy :grin:

#87

It would be awesome to have an FI C6 S6, donā€™t think iā€™ve ever seen that done.

#88

It has been done before, but by many accounts, not very well.

Give these guys 15K and they will ā€œWhippleā€ your engine for you.

https://tony-ricci-ghek.squarespace.com/d3-s8-v10

Do a bit of searching around on this forum and be your own judge.

#89

Ah, the siren song of more power out of the V10 using unnecessarily expensive, unverified solutions. Much like bolt on Lambo parts, but I digressā€¦

#90

Always so true. Also that ā€œcompanyā€ isnā€™t even a company and that blower has blown up more than one motor on the same car. Its bolting on a nightmare with performance thatā€™s not very much faster than we are now with tune exhaust and removal of the cats.

#91

It has been a few weeks since my last update. The arrival of spring and the additional home and yard maintenance items that come with it have limited the available time I have to work on this project.

The engine went back in without any noteworthy issues. I left the front drive axles out and the suspension disconnected initially. This way I could start the engine up and confirm that there were no fluid leaks that may require the engine to come back out.

I came across my first issue when I first keyed it up after finishing the electrical and reconnected the battery. I just turned the key to the ON position and after a couple of seconds, the word ā€œSAFEā€ was displayed on the cluster where the trip meter normally appears. I thought that was strange as I have never had the immobilizer lock me out after having the battery disconnected for an extended period. I left the key in the ON position and went and grabbed my VCDS tool. I then keyed it off, plugged the HEX-NET tool in and keyed it back on. The instrument cluster remained dark and the scan tool would not connect. Battery voltage was good and all the relevant fuses metered out ok. After a bit of searching online, I found that if you turn on your hazards and high beams and press the brake pedal, VCDS can connect and you will have access to a limited number of modules. I did this and then ran an autoscan, cleared all the codes and the next time I keyed it up, the cluster came back to life. This time, ā€œSAFEā€ was not displayed in the cluster. I thought this was promising, so I turned the key to start and there was nothing.

I redid the autoscan and found it was still not connecting to some of the modules, most notably the engine, transmission and immobilizer. I had a fault code in the start access authorization module for an ā€œopen or short to ground on terminal 15ā€ A quick review of the wiring diagrams pointed to the J329 power supply relay being the likely culprit as I knew the fuses were good and I had not disconnected anything inside the car when I dropped the drivetrain. This is the ā€œ370ā€ relay under the dash on the LHS.

I removed it and connected the relay coil terminals directly to a 12V power source and nothing.

After ordering a replacement and installing it, I turned the key again to the ON position and ā€œSAFEā€ was once again displayed in the cluster. The engine will start and run for about a second before the immobilizer shuts it down. I did this about ten times so the ATF pump could draw up some of the fluid out of the pan. I started with about 3.5 L of ATF in the transmission as that is the point where it started to drip out of the filler hole. After bumping the starter about 10 times, I am only down 1.5L from what the ZF states as the capacity. I want as much ATF in the tranny that I can get in case someone inadvertently decides to take it for a ā€œspinā€.

There is a VW dealership about 5 minutes from my house. After talking with a VW tech, I found out that although they use the same software as Audi, they have to access different systems as far as the immobilzers are concerned so they cannot do anything for me. I will have to get the vehicle towed to the closest Audi dealer which is about 30 miles away.

The car is at the dealer right now and is ready to be picked up but I cannot get a flat bed in there till tomorrow night.

#92

Thatā€™s a major bummer. Please let us know why the immobilizer kicked in when you find out. I had always thought as long as you disconnect the battery there would be no issues.

#93

A few things to try that might help.

With the key can you unlock the doors.
Can you turn on the radio with key on ignition.
Try swapping the ECU location of each ECU to the other side. Its happened that the slave goes into the master harnus it will give you a safe lock.

I have had this happen in the past and I just left the key in the key on position for about 45 min. But also know that if there isnā€™t com between the dash the key and the ECU you will get an immob issue. The car starting shows the ecus are working but something isnā€™t communicating at some point.

The fact you canā€™t com with the ECU with vag com to me says thatā€™s what you have to really look into.

#94

All of the other electrical (radio,doors, seats, windows etc.) worked fine

I labeled the ECUs master and slave before I removed them from the vehicle

This was not effective

That was before I changed out the failed ā€œ370ā€ J329 power supply relay. Once I installed a new one, I was able to connect.

#95

I do not think you will find a definitive answer on this.

Before arranging to get my vehicle towed, I talked to two Audi, one VW and a local indy tech who specializes in Audi/VW. The general consensus with the immobilizer 4 system is that it is kind of hit or miss when you disconnect the battery for an extended period whether the system will go into ā€œsafeā€ mode or not when the power is restored.

#96

Will the key work to unlock the doors.

You dais the techs said system 4. I never heard of system 4.

I know its the
dash
key
ECU

But that being said. Try connecting the power and then disconnecting the power. maybe that will kick on the immobilizer.

Can you connect to the ECU in vag com now.

#97

Yes, the key will unlock the doors (both mechanically and electrically)

There are plenty of online resources for the different generations of VAG immobilizer systems

Here is one: http://wiki.ross-tech.com/wiki/index.php/Immobilizer

That was not effective

Yes, once I replaced the failed J329 relay, I can connect to all of the modules (including the engine).

The immobilizer has been reset at the Audi dealer. The engine runs and the vehicle is back on the lift in my home garage to complete the re-assembly process.

#98

Things are looking good so far.

I had it up on the lift idling for about 20 minutes last night while I topped up the ATF level. Nothing was dripping (other than the water out of the exhaust). There were also no drips on the floor under it this morning.

If I have time tonight, I will put the headlights and bumper cover back on so I can take it for a spin.

Here is a current shot of the engine bay

http://audirevolution.net/addons/albums/images/38724649.jpg

#99

amazing work eng92! now for some full car shots!

#100

Did you also replace the oil cooler? If not, how did you Determine it wasnā€™t a contributing factor for oil leak?