ECU #153 to #173

[eric1855]

If my car came with the #153 ECU (1987 325is) can I replace it with the later model #173 ECU and it work?

Just wondering.

Thanks

Eric

[M-technik-3]

plug and play..

[eric1855]

Snug.

Thanks.

[hella 325]

whats the difference?

[MarkD]

whats the difference?

A few things:

- a totally new generation of hardware in the 173, which is on one board instead of two, and more reloable

- much better software. The maps are also bigger, and much easier to modify for performance.

MarkD

[hella 325]

oh, and i should be able to hook up a new ecu in my 87 and it will do ok even if i have teh motronic 1.0 fule system and wiring harness?

[Digitalwave]

oh, and i should be able to hook up a new ecu in my 87 and it will do ok even if i have teh motronic 1.0 fule system and wiring harness?

No, you need to have Motronic 1.1 to go to the 173 box which is 1.3.

[hella 325]

did 1.1 have 2 fule pumps (b/c) i do? or was that 1.0? cuz i have a engine from a 90 (thats 1.1 right)? but the car is from 12/86 which is 1.0? and i have a 153 ecu



PS sorry if im jackin ur thread, just tell me to stop and i will

[M-technik-3]

Guys, I had a 173 box in my 87 325iS that had a 153 box. It worked just fine. It had a TMS chip and there was a noticeable differance.

[coupeowner]

You can also do the stomp test w/ the 173 ECU, not the 153.

[hella 325]

stomp test?

[coupeowner]

Do a search on how to do a stomp test (it's been a while - something like key "on" then three quick stomps on the gas pedal), but basically you can get the engine fault codes though the dash. It reads out in a series of light flashes (kind of Morse Code).