So there is no indication that making the ECU adapt to the 100 ohm MAP hack causes any problems with fuel economy. The ECU did not throw a CEL, so its not having any problems with not having enough fuel pressure to do the O2 adaption.

No hard on boost results from this AM. Don't expect that any fuel cuts are now possible for current boost settings.

What about enough fuel for on boost conditions? The ECU will have a map of permissable injector duty cycles for certain running conditions. If the duty cycle is out of bounds, then it will throw a CEL, even though the O2 sensor loop is working perfectly. This is done to ensure that the injector duty cycle can be extratrapolated to the injector demands of being on boost and at at fuel cut pressures where the system runs open loop and the O2 feedback loop is not used. All of that is done, because one could have a higher injector cycle with the off-boost O2 adaption running well, but on boost could then demand more that 100% injector duty cycle which cannot be delivered. That would translate to lean conditions on boost which is a problem. (O.T. The ECU in our TDI diesel has 25 maps that are used to make sure that operating parameters and relationships are 'in bounds'. It is quite mind boggling, and it does not even have a O2 sensor or its adaption routines.)

This is a good MPG, one of the better ones, the light side wind probably had a slight tail component. My best MPGs for the AM commute are between 32 and 33, these are rare.

posted by 207.43.195...

• T5: MBC, cold weather, fuel cuts and resistor mod, Dean, Mon, 14 Oct 2002 10:56:07
  • 100 ohms update, looking good!, Dean, Mon, 14 Oct 2002 21:07:34
    • 31 MPG with 100 ohms on the AM commute, Dean, Tue, 15 Oct 2002 09:34:22 <-- Viewing This Message
      • The more resistance the leaner it runs, ckpaden, Tue, 15 Oct 2002 09:45:45
  • Re: T5: MBC, cold weather, fuel cuts and resistor mod, SteveB, Mon, 14 Oct 2002 13:12:33
  • Dean, you are the ultimate tweaker..., Richard P., Mon, 14 Oct 2002 12:53:45
    • Re: Dean, you are the ultimate tweaker..., Dean, Mon, 14 Oct 2002 14:25:42

No Site Registration is Required to Post - Site Membership is optional (Member Features List), but helps to keep the site online
for all Saabers. If the site helps you, please consider helping the site by becoming a member.

• Prev by Date: Anyone put a aftermarket EMS in a c900?, Jake W, Tue, 15 Oct 2002 09:10:45
• Next by Date: The more resistance the leaner it runs, ckpaden, Tue, 15 Oct 2002 09:45:45
• Main Performance Bulletin Board

StateOfNine.com

SaabClub.com

Jak Stoll Performance

M Car Covers

Ad Available

The content on this site may not be republished without permission. Copyright © 1988-2024 - The Saab Network - saabnet.com.
For usage guidelines, see the Mission & Privacy Notice.
[Contact | Site Map | Saabnet.com on Facebook | Saabnet.com on Twitter | Shop Amazon via TSN | Site Donations]

Random Saabnet.com Member Gallery Photos (Click Image)