'87 2.5turbo tuning - PeachParts Mercedes-Benz Forum

babymog · #1 02-01-2006, 11:00 PM

Reading some of the threads about the ALDA and turning up the pump, have done a bit of that on Cats and Detroits, considering it on my 2.5turbo.

What purpose does the air-flow-sensor on this engine serve? If I turn up the ALDA, change wastegate settings, turn up the rack, is something in the electronics of this engine going to stop my progress? Seems like there's no feedback loop to tell the engine what it's doing like an L-jetronic for example (which is where the airflow sensor apparently came from), but most of the tuning posts seem to be in reference to straight mechanical engines.

I appreciate any education on the function of the airflow sensor and whether I can tune this like a mechanically injected engine.

- Jeff Miller
190DT

Hit Man X · #2 02-02-2006, 12:16 AM

Quote:

Originally Posted by babymog

Reading some of the threads about the ALDA and turning up the pump, have done a bit of that on Cats and Detroits, considering it on my 2.5turbo.

What purpose does the air-flow-sensor on this engine serve? If I turn up the ALDA, change wastegate settings, turn up the rack, is something in the electronics of this engine going to stop my progress? Seems like there's no feedback loop to tell the engine what it's doing like an L-jetronic for example (which is where the airflow sensor apparently came from), but most of the tuning posts seem to be in reference to straight mechanical engines.

I appreciate any education on the function of the airflow sensor and whether I can tune this like a mechanically injected engine.

- Jeff Miller
190DT

AFM is for emission control only, mine's been removed for a while now... for off-road testing only of course

This is all mechanical injection, but has an electrical idle control on my SDL. Nowhere like an L-Jet or Motronic setup at all where fueling and such are sent from. That 745i I almost own is a Motronic/AFM setup... someone finally released a kit for true MAF which is great.