difference between 153 and 173 ecu?

[noid]

As the title states what are the differences between then 153 and 173 ecu's?

[Julien]

153 is for early production 325i's.. they have a tendency to shit the bed. 173 came after until early 90s.. and i think some late late cars got the 308 or 803 ecu

[nando]

it's mostly hardware - the 153 is an insanely complicated dual board monstrosity. the 173 is functionally indentical but it uses half as many electronics.

[noid]

it's mostly hardware - the 153 is an insanely complicated dual board monstrosity. the 173 is functionally indentical but it uses half as many electronics.

insanely complicated good or insanely complicated bad?

Would it be an upgrade or atleast equivelent to go from a 153 to the 173?

[reelizmpro]

153 is 1987-1988 Motronic 1.1 - dual board

173 is 89-on Motronic 1.3 - single board. Others are 380, 525...

[DaveSmed]

insanely complicated good or insanely complicated bad?

Would it be an upgrade or atleast equivelent to go from a 153 to the 173?

Upgrade, maybe. Equivalent, definitely. Some people say the 173 DMEs idle better. They also have better performance chip availability.

[nando]

insanely complicated good or insanely complicated bad?

Would it be an upgrade or atleast equivelent to go from a 153 to the 173?

bad. it has twice as many electronics that do the same thing as the 173. basically, it has twice as many failure points. Think of the 173 as an updated, streamlined version of the 153.

[Fidhle007]

The 525 is almost the same as the 173 in functionality as well. You can use 173 chips in a 525.

[StereoInstaller1]

My car has unadjustable valves. My car idles rough...really rough.

I went from a 153 to a 173, seemed to smooth things a bit.

My e-peen did get a bit thicker. No longer, just thicker.