Audi A6 with a CJAA Common Rail

nate0031

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96 B4 Passat
Been moving a tad slower than wanted, lol. That's probably the norm for projects like this though. I'll post some pictures when I get home tonight. Keep in mind this isn't a build like others you see on here (Whitbread, TDIsyncro, 2micron, Jfettig, Andy2, etc. I'm forgetting many). It'll work great, but looks a bit more...homebrew.

The engine is in. I had to modify the EGR/heater core return line to clear the bellhousing. Which essentially was cutting it off, tapping pipe threads, inserting an elbow with copious amounts of JB-weld to ensure a seal, and painting it to prevent rust and keep it from standing out like a sore thumb. It's now only the return for the oil cooler.

I've got all four fuel filters installed as well as the pure flow kit, and the fuel system primed. She'll have a total of four fuel pumps, as I just had to add a lift pump. I was going to use the stock in tank pump, but apparently the Quattro's use a venturi pump to move fuel from the drivers side of the tank to the passenger. This creates about 25 PSI of back pressure, preventing me from regulating the lift circuit to the desired 8 PSI. I had a second pump laying around, so it'll supply the engine while the stock supplies the venturi pump. Seems like a waste, but I had the pump already so it was free, lol.
The other option would've been an adjustable returnless pressure regulator, but that cost much more than free.

I'm using the stock turbo (for now), so my tubing is funky. Intercooler piping and exhaust are finished though. I'm using both stock intercoolers. I don't know how that compares to the cooling provided by the Jetta's stock intercooler, but hopefully it's adequate.

Accessory belt drive is done. I mounted a 60-2 reluctor wheel behind the harmonic balancer. This will give a crank position signal to the stock 2.7t ECU, running the tach and any dependencies. I'm using the stock 2.7t AC compressor, so HVAC should function as stock. This also prevents me having to deal with the RCV controlled compressor from the 2010 Jetta, as the 2000 used a clutched pulley.

I'm using the stock cooling fans, as they are a completely standalone system in the 2.7t. Separate sensor and control module, I'll just be installing the stock sensor into the CJAA's coolant circuit.

According to the 2.7 manual, the 2.7t's ECU doesn't require cam position sensor data to run. It can run in a limp mode from the crank position sensor alone. Which is good, because that's all it's going to get. Whether it is still fooled into thinking it's running an engine when it sees a lack of coil packs, etc is still to be seen. Fingers crossed, things work as they should with only the crank position and a few other sensors, but I would not be in the least surprised if I have to do further tinkering with this. All in all, I just need the 2.7t ECU to give a tach signal to the cluster, give oil temp to the cluster, and let the AC compressor run. Worst case scenario, I'll make a standalone controller to do this instead.

The stock ECU will also get water, oil temp and oil level data, as I'm using the stock 2.7t water temp sender installed into a blocked off EGR cooler port, and the oil sender mounted in the oil pan. I used the AWM oil pan, which had the sensor location already present, and the 2.7t sensor bolted right in.

I also ended up using the CJAA windage tray. I just trimmed the tabs and stuck it in. Fit perfectly with the AWM pan.

I'm sure I'm missing allot, but I'll add more when I post pictures. First start will be soon, hopefully this week. Fuel system is done, so now I need to prime it with oil and start hooking up the wiring. The harness is all cut down and ready, so I'll be hooking it and the glow plug module up, then looking through VCDS and doing output tests to confirm things are working as they should. I've already connected via VCDS and tested the accelerator pedal and cycled fuel pumps, so it's coming. Once that's done, I should be able to turn the key (er, touch a few wires together) and hear it run.

After I get it on the road, there will be more to follow, mostly getting warning lights off and cruise control working. Cruise will happen one of two ways. The first (and preferable) will be programming a controller to communicate with the ECU directly. I have a friend with a 2010 Jetta TDI, who's going to let me tap into and log the powertrain CAN bus while he drives. After I decipher that data, I should be able to program a controller to take in standard sensor data and emulate the other devices the ECU expects to see on the powertrain CAN. For instance, the ABS controller for VSS. Hopefully with this, the ECU will allow the stock cruise to work. The device would work both ways, I'd be able to pull CAN data from the ECU and output it as an analog signal or a PWM signal to drive a gauge. If this doesn't work, I'll simply make a controller to intercept the TPS signal from the accelerator pedal, and use a PID controller to modify it for the cruise control. There would be a host of safeties on this to prevent any undesired acceleration. The function would be transparent to the user.

But yea, that's where I'm at. Once I started doing this, I realized how little time there actually is on nights and weekends. Something else always comes up and needs attention. Case in point, the wife's BRM's cam wore out, so I'm changing that out last weekend. I'm just thinking about getting this done so I can continue on my car. Like a bad joke, I hear a loud bang, followed by more, rapid, loud metallic banging. I duck, thinking somethings about to fall on me, or otherwise cause severe bodily harm, lol. Turns out, the torsion spring on the garage door right behind me snapped, and the thing unwound. Scared the crap outa me. But alas, another thing to fix...
 
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nate0031

Veteran Member - TDIClub Contributor
Joined
May 14, 2012
Location
SE Ohio
TDI
96 B4 Passat
Here are some pictures. First, the reluctor wheel:



Here's the belt system overall:



Here is the turbo side: You can see the downpipe and the turbo discharge pipe going into the intercooler.



Overall under the hood shot:



Intake and fuel side:



More intake and fuel side:



I'll clean the hoses and wiring up a bit. After it's all running, I'll likely get the tubing bender out and replace most the rubber hose with hard tubing.
 

nate0031

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SE Ohio
TDI
96 B4 Passat
Probably worth noting, the first filter is a 14 micron filter and water separator, the second is a 2 micron filter. From there it goes to the stock filter (5 micron?) which I primarily kept for the thermostatic fuel valve, which still resides in the filter housing if I'm not mistaken. The other filter is the same 1 micron Bio-Tek (Cim-Tek) filter used in the Return Flow kit. I mounted it on a standard base from Fleet Filter since 2microns kit wouldn't fit in this application. The two rear filter bases are NAPA 4770's, I'd have to dig up the number for the return filter base.

Fuel will continuously cycle through the two large filters. Hopefully it is rather polished by the time it goes to the engine. If the filters become restrictive before 20k miles, I'll re-plumb the regulators location to make them not also filter fuel that will be returned to tank.
 

TDIsyncro

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Nov 14, 2005
Location
Saskatoon, SK
TDI
Audi/TDI x 2
Hey nice update. I will admit I toyed with the idea of using factory turbo and piping up just like you...just to save some hassle. How did you end up with the steering pump? did you buy the euro A6 TDI bracket?
four filters!:eek:
interesting concept for keeping all your factory tach, instrumentation. I am a bit jealous of you ability to capture and understand CAN data. :cool:
 

nate0031

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Location
SE Ohio
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96 B4 Passat
Thank you. Yea I might've over done it with filtration a tad, lol. My biggest concern with this engine was the HPFP, so I wanted decent assurance that it'd always get good clean fuel. Then I used Andrews kit so that if the pump still failed at some point, the rest of the system is spared. At that point I'd swap to a cp3 and be done.

For the accessories, I believe I got the same bracket as you from a 2010 A4. Worked perfectly. The power steering pump uses the same bolt pattern.
 
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nate0031

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SE Ohio
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96 B4 Passat
Re-watching, that video isn't of the best quality, lol. I'll post more soon as things start getting buttoned up.
 

TDIsyncro

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Nov 14, 2005
Location
Saskatoon, SK
TDI
Audi/TDI x 2
great to see it running. I don't think anybody is thinking about it being redneck. You have one of the first transplanted CR engines running!:cool:
 

nate0031

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SE Ohio
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96 B4 Passat
Well after months of trial and difficulty getting this to work, I've decided to give up.

Just kidding. Took it for it's maiden drive last night, all seems to work well. Feels strong, so I don't think limp mode is an issue here. I'm not certain how limp mode works and what it restricts, but it happily and quickly spooled to 22 PSI of boost. I would think limp mode would greatly restrict this.

The drive was short, as it popped off one of my boost pipes. I'm quite happy though, as I had resolved myself to troubleshooting limp mode issues. This doesn't appear to be the case at all, and I can fix a pipe easy, lol.

I used the A6 accelerator pedal, as the ranges and scaling seemed quite similar, I just altered both end stops to give me a full 0-100% in VCDS. Works perfectly and saved me from trying to integrate the floor mounted accelerator.

The tach on the cluster works well. Seems the 2.7t ECU doesn't mind that only a few wires are hooked up. Seems to fool it into believing it's running, as it starts tossing alarms for oil pressure/level and coolant level as soon as I fire it up. As long as it runs the AC as it should, I'm good to go there.
 

nate0031

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SE Ohio
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96 B4 Passat
Well, drove it to work for the first time this morning, and made it. It's about 30 miles/35 minutes. Drove great. Had great power, car doesn't feel bulky at all. Can't wait to see what it gets on the gallon, no doubt 2-3 times what the Excursion was getting, lol.

Had another boost pipe blow off the other day, so I beaded the ends of all the metal tubing and the issue seems resolved. Held it at full throttle several times in higher gears, boost holding a steady ~20-21 PSI, and they all held on, lol. IAT at this point was about 18°F more than ambient. I got a pair of crimpers from Lowe's for $10, chopped the tip/wire cutter section off, then used the crimping section to bead the tube. One crimp at a time. All the way around. My hands are sore, lol.

Power steering works great, alternator is charging, and I think the coolant system is burped. Got about 2.5 gallons in of the nice green Prestone (J/K, G-12). Holds a steady 90C on the highway. So it seems to be setting pretty well right now.
 

nate0031

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SE Ohio
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96 B4 Passat
Interesting that the ECU is running the tach. Is it also controlling the A/C pump as you hoped?
Yea, so far it seems pretty happy to do so. So far I have a check engine and EPC light, but the tach, speedo, water temp, and battery gauges all work. The oil temp doesn't seem to be working though.

I haven't had a chance to charge the AC yet, so still crossing my fingers for that one, lol. I'll post up one way or the other once I do.
 

Rafedial1

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Dec 18, 2014
Location
Vermilion, OH
TDI
2003 Jetta TDI
Yea, so far it seems pretty happy to do so. So far I have a check engine and EPC light, but the tach, speedo, water temp, and battery gauges all work. The oil temp doesn't seem to be working though.
I haven't had a chance to charge the AC yet, so still crossing my fingers for that one, lol. I'll post up one way or the other once I do.
Nice project and thread. Dedicated, great work! Have a family member with A6 2.7T, your car makes me think what if?

Where are you in SE Ohio? Driving through there about Friday mid aft/evening and would love to see the car. On my way to Tennessee and back. let me know.
 

nate0031

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96 B4 Passat
Thank you guys! mtushmoo, I'll pull up my fuel tank pictures and respond in your thread. Sent you a PM Rafedial.
 

vw_nut

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Joined
Jun 22, 2005
Location
Beechgrove, TN, 37018
TDI
, 1981 VW pickup TDI Conversion, , 2000 Golf TDI,1985 Cabriolet 16V,2006 jetta
Your build gave me the inspiration to think about a common rail swap in the mk2, I've enjoyed your build nice work
 

nate0031

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SE Ohio
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96 B4 Passat
Been a busy few weeks, haven't had time to post much. Apparently there were two different accumulator styles for that car, and I got the wrong one. Just received the correct one, so we'll see if AC works this weekend.

I have just under 800 miles on it now and I have run it to about a half tank twice then filled. I was way to curious about mileage to let a full tank go through, lol. The first time, with my erratic test driving and about 70/30 highway/city, fetched 38 MPG. The second time with easier driving, no full throttle testing but on the same 70/30 commute to work, got 40.3. I'm pretty happy, and that's on snow tires too. The highway is cruising at (about, no cruise yet) 65 MPH at ~2500 RPM. I'm really hoping to get even more into the low 40's when I get new tires next month, something more touring oriented with a harder compound and 10mm narrower. We'll see though. Between that and a swap to a euro trans, I think it'll do pretty well for itself.
 

nate0031

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Nice weather last weekend, so we took the car for a nice drive. Snapped a couple pictures:



 

nate0031

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SE Ohio
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96 B4 Passat
Got the AC working. Looked at the AC controller and the compressor shutdown code indicated that the ECU was not giving it permission to engage, likely because of the smorgasbord of errors.

There are three wires going from the ECU to the AC control head. The schematics aren't in front of me, so double check these. One, located on T10p if memory serves, is the tach signal. The other two, T17k/2 and T17k/3, are for the control head asking permission from the ECU to engage the compressor. It wouldn't do it without a tach signal, but with the tach, when the AC was commanded on by the controls in the cab, the control head would send 12 volts to the ECU on the black/yellow wire (T17k/2). Meanwhile, the black/gray wire (T17k/3) would stay at 0. I had a hunch that wire was supposed to go high (to ~12 volts) to let the control head know it was allowed to engage the compressor. I connected those wires directly to each other and sure enough, the compressor shutdown code changed and the compressor kicked on. So I disconnected them from the ECU and soldered them directly to each other. Now when the control head sends 12 volts to request to engage the compressor, it sees it's own signal and thinks the ECU is giving it the go ahead.

I charged it like normal and now it's nice and cold. Now to fix the cruise.
 

TDIsyncro

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Saskatoon, SK
TDI
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Got the AC working. Looked at the AC controller and the compressor shutdown code indicated that the ECU was not giving it permission to engage, likely because of the smorgasbord of errors.

There are three wires going from the ECU to the AC control head. The schematics aren't in front of me, so double check these. One, located on T10p if memory serves, is the tach signal. The other two, T17k/2 and T17k/3, are for the control head asking permission from the ECU to engage the compressor. It wouldn't do it without a tach signal, but with the tach, when the AC was commanded on by the controls in the cab, the control head would send 12 volts to the ECU on the black/yellow wire (T17k/2). Meanwhile, the black/gray wire (T17k/3) would stay at 0. I had a hunch that wire was supposed to go high (to ~12 volts) to let the control head know it was allowed to engage the compressor. I connected those wires directly to each other and sure enough, the compressor shutdown code changed and the compressor kicked on. So I disconnected them from the ECU and soldered them directly to each other. Now when the control head sends 12 volts to request to engage the compressor, it sees it's own signal and thinks the ECU is giving it the go ahead.

I charged it like normal and now it's nice and cold. Now to fix the cruise.
nice diagnostics going on there. Its great to find simple solutions like that.:) The euro TDI 01E will make a very nice upgrade and go along way to your mpg goals.
 
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nate0031

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SE Ohio
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96 B4 Passat
nice diagnostics going on there. Its great to find simple solutions like that.:) The euro TDI 01E will make a very nice upgrade and go along way to your mpg goals.
Thanks! Yea, I can't wait to do the tranny swap. This one isn't bad, but I know it'll be way better with proper ratios.
 

iwannajettatdi

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2015 Brilliant Black Audi Q5 3.0TDI, 2014 Tempest Blue metallic Jetta Sportwagen TDI, 2002 Blue Eurovan Weekender BHW TDI
Nate,

I have a few questions for you. PM'd you. Sweet swap! How are things rolling along now? Any more long term MPG reports?
 

mr_y82

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May 19, 2013
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Western NC
TDI
Used to have... '11 Golf, 6-spd, 2-door
One does not...
simply make a controller to intercept the TPS signal from the accelerator pedal, and use a PID controller to modify it for the cruise control.
...You guys never cease to amaze me, lol

Great swap!

I got a pair of crimpers from Lowe's for $10, chopped the tip/wire cutter section off, then used the crimping section to bead the tube. One crimp at a time. All the way around. My hands are sore, lol.
I bet...
 

nate0031

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96 B4 Passat
Responded to your PM. Thanks everyone. Been great so far. Right now I'm getting 37-38 when mostly city/short trips. 41 on the highway going 70-75. Got 17 towing the 26ft camper at 60 weighing 4200lbs, 28 when towing the 17ft flat utility trailer, ~1500 lbs. And 32 pulling the jet ski, ~600 lbs.

I've put just over 10k on her so far. No issues yet. Looking to upgrade the clutch soon and hopefully get a euro TDI box in there.
 

mcneil

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2010 Golf TDI 4dr, 2001 Jetta TDI, Jeep TDI project
Great swap!
Did you ever get cruise working with the VSS over CAN? If so, what's the CAN ID for speed and how is it formatted?
 

TDIsyncro

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Location
Saskatoon, SK
TDI
Audi/TDI x 2
Responded to your PM. Thanks everyone. Been great so far. Right now I'm getting 37-38 when mostly city/short trips. 41 on the highway going 70-75. Got 17 towing the 26ft camper at 60 weighing 4200lbs, 28 when towing the 17ft flat utility trailer, ~1500 lbs. And 32 pulling the jet ski, ~600 lbs.

I've put just over 10k on her so far. No issues yet. Looking to upgrade the clutch soon and hopefully get a euro TDI box in there.
Glad it is running great for you. The fuel mileage sure dips down when pulling. I was surprised to see it go down that much for flat trailer, but I guess a 17ft is pretty big. Nice job pulling the 26ft camper behind A6 TDI! :D
 

nate0031

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SE Ohio
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96 B4 Passat
Great swap!
Did you ever get cruise working with the VSS over CAN? If so, what's the CAN ID for speed and how is it formatted?
I haven't yet. Just got my replacement Raspberry Pi to keep working on it. I am rigging up a simple Arduino solution at the moment that'll use a PID controller to alter the accelerator signals to the ECU. That'll get me cruise in the meantime, I'm really missing it, lol. When I get a chance I'm going to log the CAN traffic on a friend's 2010 TDI and figure out the needed ID's and format. I'll need to figure out the ID's from the steering wheel module as well, as the cruise commands from the stalk are sent to the ECU via CAN.
 

nate0031

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May 14, 2012
Location
SE Ohio
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96 B4 Passat
Glad it is running great for you. The fuel mileage sure dips down when pulling. I was surprised to see it go down that much for flat trailer, but I guess a 17ft is pretty big. Nice job pulling the 26ft camper behind A6 TDI! :D
Yea, it sure dips down with the camper, lol. Still about 65% better than with the excursion and 7.3. I feel like the Excursion should be getting better than it is (about 11), but even going slow didn't seem to have a significant impact. Might just be how it is with the heavy aerodynamic load that comes with the camper.

I was expecting a few better with the utility trailer too, wondering if the aero load from the taller furniture or the extra axle is what pulled it down.

What he says. :D
I was looking around for more CANBUS ID's. Only have a couple right now.
I'll be sure to post them up when I get them. Which ones do you have so far?
 
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