2011 Audi A4 B8 - ALH TDI Conversion

drkblujetta

Veteran Member
Joined
Jan 31, 2007
Location
Venus
TDI
2011 Audi A4 ALH TDI
This car was intended to serve one purpose. A reliable , AWD commuter, that maintains excellent fuel economy.
Living at a higher elevation with snow and leaving early for work before the plows come means our 2000 Jetta TDI is not the right tool for the job. (Abandoning it at the bottom of the hill sucks)

So, we bought a cheap cheap 2003 golf a few years back with the intention to convert our Allroad to a tdi. That didnt happen.

Fast forward to now. We found a 2011 A4 AWD with a blown motor for a smokin deal. Without a conversion anywhere on the internet to be found, we went ahead and winged it. haha

This project is a budget project, and we re-used most of the 2.0L bits and pieces (mainly hoses, sensors, etc.)

I cannot break everything down step by step, but will give an outline of some of the challenges we faced, European parts we needed, and general modifications.

Disclaimer. You do require some fabrication skills , mainly engine mounts/downpipe/intercooler pipe etc.

Here goes with some highlights/issues we had to overcome:

-Flywheel bolt pattern. We re-used the 2.0t flywheel. (YOU HAVE TO ) It fits perfectly onto the alignment hub on the alh crank. It was 8 holes, the ALH is 6. We welded up holes, and drilled new pattern to fit ALH crank, then put it on a lathe.

-Starter . The 2.0t starter is not large enough. (it wont live long turning the diesel engine over . Had to import a 2.0 diesel starter from a b8 tdi from europe. (pic below for size comparison)

-Turbo. The ALH turbo interferes with starter. Therefore you need to source a longitudinal turbo from passat / audi diesel.. Bought a 1749VA from europe to make it work.The turbo also puts an almost perfect placement for a straight downpipe to existing 2.5" exhaust system ;)

-Intake. ALH Intake inlet facing the wrong , not enough clearance for intercooler piping on the front of the motor. Bought a PD130 intake from Europe. Works great, and much larger/better flow.

-Custom Fabricated engine mounts to utilize the OEM rubber mounts. Used steel solid stock, drilled and tapped to maintain stock rubber mounts/hardware. Also required for starter/turbo clearance.

-Power steering line welded to alh bango to utilize alh PS pump. Works fine.

-90% of the coolant lines were plumbed using 2.0t and ALH donor lines. (very little $ spent in this area. Made a hose reducer and integrated the 2.0T coolant temp sensor to maintain control of the dash. Coolant temp on dash works.
Retained factory radiator, and reservoir.

-Tach signal: 2.0t reluctor wheel which was on the crank internally, removed, and welded to the front crank pulley. Perfect match for the outside circumfrence of the crank pulley which allows for perfect alignment for welding. Made bracket to mount externally and utilized 2.0t factory crank position sensor.. Tach signal works..

-Speedo still relies on Left front ABS , still works never touched it .

-Oil pressure sensor works, 2.0T plugs right in. (same sensor) Dash works

-Oil pan. ALH will not clear PS rack. Had to replace with 1.8T oil pan & pu tube. Factory 2.0T oil sending unit bolts to the bottom.

-Factory airbox retained. Modified oem MAF housing to accept ALH MAF. ALH MAP sensor bolted right into the place of the 2.0t location/existing intercooler piping.

-Turbo outlet to the intercooler piping was retained by using the ALH pancake pipe quick connect hose. Used hose joiner to connect to 2.0t intercooler.

-Factory front mount Intercooler stayed OEM. The piping up top made with 2 1/4" exhaust tubing and rubber factory elbows from the 2.0t. The theme in this swap, re-using alot of 2.0t stuff.

-Fuel system plumbed into the existing lines with some small modifications at the sending unit where the pump was bypassed. Made quick charcoal cannister bypass with piece of 3/4" hose

-Throttle pedal from ALH was bolted to the Audi, but had to change the angle of the pedal -cut and weld(see pic below)

-Factory ECU left in place. Removed all non-used engine sensors and dead headed the wires.

-Utilized TDI Alternator, only 1 wire from Audi side, plugs in for the dash light. (works)

-TDI Harness stripped to just whats required to make engine run (stand alone) Immobilizer , EGR and ASV deleted from ecu. Malone tuning.

-Engine runs by itself, engine vitals monitored by original Audi sensors & work in dash.

-ABS and Quattro system functionally well.

-CEL on. (Shocker)

-Stability Control Light on because throttle body isnt hooked up, it cant kill the throttle . ( not that we care) lol

-No cruise control, haven't tried to figure that out yet.

-Complication. Both cooling fans are runing all the time as soon as you fire engine up. (working on fixing that quernk)

-Still have to make custom AC lines to ALH compressor.

-E brake fault warning. But E brake still works. Because factory design will automatically release the ebrake when you give it throttle. Factory throttle input not connected.

Everything in the rest of the car functions (Interior functions/ Radio/ Heater/ dynamic steering, etc. is happy)

Mods on the TDI include an old school tuning box and TPC for proof of concept. May consider getting ECU flashed. PD130 intake and vnt 17

Car is not disappointing to drive at all. Very impressed with overall road manners, Gearing etc.

Clutch and 6spd manual Trans feel great.

Worth the effort. Alot of head scratching, and thinking outside of the box .

This swap is function over finish, but the end result was we made the swap work with $1500 (including $400 parts car) Utilizing existing parts was huge, shopping ebay etc...

Now we want to find a b8 Avant. :)


Flickr has the photos. Too painful to upload here.

https://www.flickr.com/photos/185872119@N08/

thumbnail_image1 (1) by drkblujetta Smith, on Flickr
 
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Jewski13

New member
Joined
Oct 3, 2022
Location
East Peoria, IL
TDI
2003 ALH Jetta
This car was intended to serve one purpose. A reliable , AWD commuter, that maintains excellent fuel economy.
Living at a higher elevation with snow and leaving early for work before the plows come means our 2000 Jetta TDI is not the right tool for the job. (Abandoning it at the bottom of the hill sucks)

So, we bought a cheap cheap 2003 golf a few years back with the intention to convert our Allroad to a tdi. That didnt happen.

Fast forward to now. We found a 2011 A4 AWD with a blown motor for a smokin deal. Without a conversion anywhere on the internet to be found, we went ahead and winged it. haha

This project is a budget project, and we re-used most of the 2.0L bits and pieces (mainly hoses, sensors, etc.)

I cannot break everything down step by step, but will give an outline of some of the challenges we faced, European parts we needed, and general modifications.

Disclaimer. You do require some fabrication skills , mainly engine mounts/downpipe/intercooler pipe etc.

Here goes with some highlights/issues we had to overcome:

-Flywheel bolt pattern. We re-used the 2.0t flywheel. (YOU HAVE TO ) It fits perfectly onto the alignment hub on the alh crank. It was 8 holes, the ALH is 6. We welded up holes, and drilled new pattern to fit ALH crank, then put it on a lathe.

-Starter . The 2.0t starter is not large enough. (it wont live long turning the diesel engine over . Had to import a 2.0 diesel starter from a b8 tdi from europe. (pic below for size comparison)

-Turbo. The ALH turbo interferes with starter. Therefore you need to source a longitudinal turbo from passat / audi diesel.. Bought a 1749VA from europe to make it work.The turbo also puts an almost perfect placement for a straight downpipe to existing 2.5" exhaust system ;)

-Intake. ALH Intake inlet facing the wrong , not enough clearance for intercooler piping on the front of the motor. Bought a PD130 intake from Europe. Works great, and much larger/better flow.

-Custom Fabricated engine mounts to utilize the OEM rubber mounts. Used steel solid stock, drilled and tapped to maintain stock rubber mounts/hardware. Also required for starter/turbo clearance.

-Power steering line welded to alh bango to utilize alh PS pump. Works fine.

-90% of the coolant lines were plumbed using 2.0t and ALH donor lines. (very little $ spent in this area. Made a hose reducer and integrated the 2.0T coolant temp sensor to maintain control of the dash. Coolant temp on dash works.
Retained factory radiator, and reservoir.

-Tach signal: 2.0t reluctor wheel which was on the crank internally, removed, and welded to the front crank pulley. Perfect match for the outside circumfrence of the crank pulley which allows for perfect alignment for welding. Made bracket to mount externally and utilized 2.0t factory crank position sensor.. Tach signal works..

-Speedo still relies on Left front ABS , still works never touched it .

-Oil pressure sensor works, 2.0T plugs right in. (same sensor) Dash works

-Oil pan. ALH will not clear PS rack. Had to replace with 1.8T oil pan & pu tube. Factory 2.0T oil sending unit bolts to the bottom.

-Factory airbox retained. Modified oem MAF housing to accept ALH MAF. ALH MAP sensor bolted right into the place of the 2.0t location/existing intercooler piping.

-Turbo outlet to the intercooler piping was retained by using the ALH pancake pipe quick connect hose. Used hose joiner to connect to 2.0t intercooler.

-Factory front mount Intercooler stayed OEM. The piping up top made with 2 1/4" exhaust tubing and rubber factory elbows from the 2.0t. The theme in this swap, re-using alot of 2.0t stuff.

-Fuel system plumbed into the existing lines with some small modifications at the sending unit where the pump was bypassed. Made quick charcoal cannister bypass with piece of 3/4" hose

-Throttle pedal from ALH was bolted to the Audi, but had to change the angle of the pedal -cut and weld(see pic below)

-Factory ECU left in place. Removed all non-used engine sensors and dead headed the wires.

-Utilized TDI Alternator, only 1 wire from Audi side, plugs in for the dash light. (works)

-TDI Harness stripped to just whats required to make engine run (stand alone) Immobilizer , EGR and ASV deleted from ecu. Malone tuning.

-Engine runs by itself, engine vitals monitored by original Audi sensors & work in dash.

-ABS and Quattro system functionally well.

-CEL on. (Shocker)

-Stability Control Light on because throttle body isnt hooked up, it cant kill the throttle . ( not that we care) lol

-No cruise control, haven't tried to figure that out yet.

-Complication. Both cooling fans are runing all the time as soon as you fire engine up. (working on fixing that quernk)

-Still have to make custom AC lines to ALH compressor.

-E brake fault warning. But E brake still works. Because factory design will automatically release the ebrake when you give it throttle. Factory throttle input not connected.

Everything in the rest of the car functions (Interior functions/ Radio/ Heater/ dynamic steering, etc. is happy)

Mods on the TDI include an old school tuning box and TPC for proof of concept. May consider getting ECU flashed. PD130 intake and vnt 17

Car is not disappointing to drive at all. Very impressed with overall road manners, Gearing etc.

Clutch and 6spd manual Trans feel great.

Worth the effort. Alot of head scratching, and thinking outside of the box .

This swap is function over finish, but the end result was we made the swap work with $1500 (including $400 parts car) Utilizing existing parts was huge, shopping ebay etc...

Now we want to find a b8 Avant. :)


Flickr has the photos. Too painful to upload here.

https://www.flickr.com/photos/185872119@N08/

thumbnail_image1 (1) by drkblujetta Smith, on Flickr
Just curious as I may be buying a B7 A4 2.0T that a buddy has been swapping an ALH into. He has it running and driving but it has a standalone harness and a 2nd ECU. Do you only have one ECU? I'm curious if the cruise would work as it would be my daily commuter and hate lights but traction control isn't too bad for me. Interested because IK you can use the ALH ecu on a B6 swap but think the B7 is all canbus.
 

JordanTr

Veteran Member
Joined
Mar 28, 2022
Location
Kimberley, BC
TDI
1996 B4V x2, 2006 Dmax, 2005 Allroad, 2005 BHW
OP stated that the car has 2 ECUs.

-Factory ECU left in place. Removed all non-used engine sensors and dead headed the wires.
 

adamss24

Veteran Member
Joined
Nov 2, 2005
Location
Great Britain
TDI
audi a4 2.5 tdi 98 quatrro 6speed
I don’t understand this nonsense, ALH was (still is) a great engine 20 years ago but why not made it a CR ? It’s miles ahead of the ALH, it’s not too complicated and has great fuel efficiency especially with a remap/tune !
I don’t see the appeal, it’s horses for corses but to me it’s a lot of work for not much gain other than for simplicity sake !
Great effort but not really worth it in my honest opinion!
 

T1MMBOJONES

Veteran Member
Joined
Nov 10, 2020
Location
Milwaukee
TDI
2013 CJAA JSW/DSG
I don’t understand this nonsense, ALH was (still is) a great engine 20 years ago but why not made it a CR ? It’s miles ahead of the ALH, it’s not too complicated and has great fuel efficiency especially with a remap/tune !
I don’t see the appeal, it’s horses for corses but to me it’s a lot of work for not much gain other than for simplicity sake !
Great effort but not really worth it in my honest opinion!
im a tad confused also, this reminds me of the guy who put an IDI 7.3l in a 2008(ish) super duty that previously was 6.4l, granted the 6.4l is garbage and i understand not wanting one... but yeah as much as i loved my alh i enjoy my cr a lot more...still an impressive project nontheless
 

T1MMBOJONES

Veteran Member
Joined
Nov 10, 2020
Location
Milwaukee
TDI
2013 CJAA JSW/DSG
I don't think the 7.3 IDI could even free rev, with one of the 6.4's turbos, without sheering the crank in half.
i didnt say he put a turbo
on it....it was a truck with a blown 6.4 of which he pulled and replaced with an idi. i believe he retained whatever trans it had also (zf5?) basically when it was all said and done theonly real creature comfort he had was the interior if you will, nothing else actually functioned. this dude at least has a fully functional audi....
 

strickenchips

Member
Joined
Mar 2, 2023
Location
Vancouver Island, BC
TDI
MkIV VW Jetta, B5.5 VW Passat 4motion (Soon to be TDI)
I know you didn't say that. I'm just saying the only reason the 7.3 has the reputation it does is because it doesn't even make enough power to blow up. The 6.4 is fine once deleted.

Oh for sure. After reading about one other guy trying to EA189 swap his B8, I can't blame this guy for making the ALH work.
 

T1MMBOJONES

Veteran Member
Joined
Nov 10, 2020
Location
Milwaukee
TDI
2013 CJAA JSW/DSG
I know you didn't say that. I'm just saying the only reason the 7.3 has the reputation it does is because it doesn't even make enough power to blow up. The 6.4 is fine once deleted.

Oh for sure. After reading about one other guy trying to EA189 swap his B8, I can't blame this guy for making the ALH work.
got ya, deleted or not i would never own a 6.4l but yes most the reason the 7.3l PS and idi last as long as they do is like you stated they dont create enough power to self destruct. the 6.0l has proven to be a somewhat reliable engine if everything is addressed but youre the first person ive ever heard say a good thing about a 6.4l but this aint the place to
debate that i suppose....
 
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