Let's get technical: Tuning the ECU for mpg

[ashiga]

I just raised the closed loop threshold (throttle position x rpm) for all values on my D16Z6 P28 ECU with chrome, I'm hoping to get better mileage as I'm a hard driver but I usually keep my foot below WOT. I changed the threshold values to about 80%. That's an idea I just had, so I'll tell you if I get bad mileage which I think is unlikely to occur as when I had a wideband, the stock basemap produced 12.5 AFR when in open loop.

[pgfpro]

I hate closed loop.

Have you tried running only open loop and build your own fuel/ign. maps. You can dial your tune in way better then stock when running in closed loop as long as you have a wideband for reference. Major gains can be made over stock by running in open loop with a good map.

[ashiga]

Originally Posted by pgfpro

I hate closed loop.

Have you tried running only open loop and build your own fuel/ign. maps. You can dial your tune in way better then stock when running in closed loop as long as you have a wideband for reference. Major gains can be made over stock by running in open loop with a good map.

I sold my wideband some time ago, but the point in raising the tps threshold is that it would switch into open loop only when I wanted performance (as I do want performance sometimes). Also as stock ecu does not accept 2 maps running at the same time (one map for performance and the other for economy) which is what I'd really want.
Apparently I had no significant improvement in raising the TPS, but I don't know whether it did or it didn't work. I've got stuck into HUGE traffic jams these days (12 miles in 1,5 hour).

[pgfpro]

Originally Posted by ashiga

I sold my wideband some time ago, but the point in raising the tps threshold is that it would switch into open loop only when I wanted performance (as I do want performance sometimes). Also as stock ecu does not accept 2 maps running at the same time (one map for performance and the other for economy) which is what I'd really want.
Apparently I had no significant improvement in raising the TPS, but I don't know whether it did or it didn't work. I've got stuck into HUGE traffic jams these days (12 miles in 1,5 hour).

You can have your performance and economy too. All you have to do is run the engine lean in light load and normal in mid to heavy load. All of this is of course based on your MAP sensor.