# s4 engine swap



## jazzb5s4 (Dec 10, 2009)

hello i have a 01 s4 engine with 80k...my uncle is giving me an o1 a4 with a bad engine its 5 speed i was wondering if the 5 speed manual will bolt on to the 2.7t engine. i have the ecu for that engine but dont have the key...basically what i am trying to find out is if the 2.7t engine i got will work on the a4 do i have to swap ECU's and will the a4 key work with the s4 harness


----------



## Peter Badore (Jun 17, 2002)

jazzb5s4 said:


> hello i have a 01 s4 engine with 80k...my uncle is giving me an o1 a4 with a bad engine its 5 speed i was wondering if the 5 speed manual will bolt on to the 2.7t engine. i have the ecu for that engine but dont have the key...basically what i am trying to find out is if the 2.7t engine i got will work on the a4 do i have to swap ECU's and will the a4 key work with the s4 harness


 The B5 S4 for the US market does not has an immobilizer. If you have all the S4 engine compartment wiring and understand the differences in the A4 to S4 body and chassis wiring you should be OK, but I have not done this swap yet. The B5 S4 does have differences between manual to automatic transmission cars for the use of secondary air injection among others changes.


----------



## GRMNMUSL (May 22, 2009)

Yes it will work once car is a a 2.8. Use S4 ECU and wiring harness. S4 Power steering hose that runs under intake from the back, use A4 2.8 AC line in front by snub (because it wont pull) and the S4 one that goes under. Speed sensor is a 4 pin on S4 and a 5 pin on A4. You just have to jump one pin. Use 2.8 Clutch stuff South Bend works well. Thats it FYI..gears are longer
on 2.8 Trans it pulls better. Any questions PM Me.


----------



## GRMNMUSL (May 22, 2009)

BTW...Do not disassemble anything it goes right in and put in NEW Engine mounts when motors out as inlets run right above them and when in car 4-5 hr job due to space.


----------

