Originally Posted by
kingtj
Yeah... all of that makes sense to me too. I'm pretty sure signal modifiers aren't viable anymore for modern ECUs and all of their sensors, if you're trying to do anything having to do with enriching closed loop settings or even fooling an ECU into advancing timing based on an alternate map or maps.
I went through some of that when I had my Hyundai Genesis Coupe V6. I foolishly paid over $450 for a "fuel controller" module from a place called Road Race Motorsports. It had plug and play harness connections to place itself in front of the MAF sensor and supposedly had a custom AFR map programmed into it, so it could lean out the overly rich defaults used in the factory maps -- gaining some power and saving gas at the same time.
Sounded good on paper, except in reality? The ECU was smart enough to learn around its changes over time. Basically, it had enough other sources of data input so it could see something had changed, and after 40-50 miles of driving, the improvements the box gave you initially were always negated (until you pulled the battery terminal and forced a reset, anyway).
I've become a big believer that with today's cars, you have to re-flash the ECU (and probably also the TCU) to make any worthwhile changes. This E85 box *may* also be this way, except I think it may actually work in this scenario because they're not attempting to trick anything to improve performance. They're basically keeping the ECU "content" that it's making its own adjustments within its usual tolerances, and getting back results that tell it the adjustments had the expected results.
Originally Posted by
tunaglove
I think you are right.
I tried doing that with a Split Second enricher. The ECU is hard to fool.
If you are trying to fool the ECU by manipulating the MAP sensor voltage so the car thinks the load is different than it really is, you will have issues as the new cars will learn around it. I have been successful with the new Hemi's by using pulse width modulation control of the fuel injectors directly. The ECU never sees it and does not learn around it. The unit I have used is similar to the AEM unit, but much easier to use as it is programmed in miliseconds of fuel pulse and degrees of timining. The AEM uses percentages which is more difficult to comprehend.
The unit I have used is the iEMS3 (Integrated Engine Management System 3). MAP sensor voltage skewing is old school ECU manipulation, and worked pretty good before the advanced OBDII ECU's came out.
I have been successful in control of closed loop fuel AFR's by applying an O2 sensor voltage offset. The ECU sees it as a lean condition and adds fuel to bring it back to what it "thinks" is the correct 14.7 AFR. I have used this for part throttle boost fuel control while still in closed loop and it works very well. I can control AFR to within .2 to .4 of my target which is fine for light load part throttle boost on a turbo.