Hi I have a query recently converted autobox to manual and still using the Auto ECU (Non CAT). Have an ECU from the manual car where I got the gearbox from had a sensor in the exhaust ( I guess due to a CAT fiited) can I use this ECU to repalce the Auto ECU without having the CAT?
Any advice greatly appreicated
Chas
M40 1.6 with 1.8 ECU
Moderator: martauto
- Brianmoooore
- E30 Zone Team Member

- Posts: 49358
- Joined: Mon Jan 10, 2005 11:00 pm
All ECUs are suitable for use with or without a cat, although some late AFMs don't have a CO adjuster, so can't be used without a lambda sensor.
If you've removed a cat from a M40 engined car, there are two white/black wires under the bulkhead wiring cover, which have to be plugged together to connect up the CO pot on the air meter.
If you've removed a cat from a M40 engined car, there are two white/black wires under the bulkhead wiring cover, which have to be plugged together to connect up the CO pot on the air meter.
Hi thank you for your update I did not remove the CAT (the cat car does not have lambda sensor) I have a ECU from a car that had a lambda sensor and I would like to fit this ECU into my car and would like to know how to do this. Are you able to show me a picture of where the black/white wires are located and ow to connect them together?
Chas
Chas
- Brianmoooore
- E30 Zone Team Member

- Posts: 49358
- Joined: Mon Jan 10, 2005 11:00 pm
If you haven't removed a cat (+ lambda sensor) from the car in question, then no wiring changes are needed.
Why are you trying to connect a 1.8 ECU to a 1.6 engine?
Why are you trying to connect a 1.8 ECU to a 1.6 engine?
- Brianmoooore
- E30 Zone Team Member

- Posts: 49358
- Joined: Mon Jan 10, 2005 11:00 pm
Well, this is the title of the thread: "M40 1.6 with 1.8 ECU"!Ch4ni wrote: I did not mention 1.8 ECU to 1.6 where did you get this info from?
No difference between an auto and a manual ECU.

