Husqvarna TR 650 Terra spegnimento a bassi regimi - Enduro

e' uno problema di mappatura magra, il problema dell'iniezione e' che quasi tutte sono tarate a 1:14.6 , proporzione che nessun amante dei motori si sognerebbe mai di usare per avere un rendimento ottimale. dimenticato il rendimento con certe iniezioni il problema e' addirittura quello di tenerle accese

questo link e interessante. Link a pagina di Advrider.com
ti copio sotto uno dei msg piu' illuminanti, all'inizio dice che decide il tempo in cui l'iniettore e' aperto, pertanto dovrebbe funzionare anche un inettore che spara piu' benza nello stesso tempo. non ho idea dei costi. ho visto che una soluzione del punto 3 sta intorno ai 200 dollari

In order to consider which type of fueling "enhancement" you want to invest in, and what you can expect from it, it helps to know how an ECU calculates the amount of fuel (length of time the injector is pulsed open). Below is a simple outline of how the Bosch/BMW Motronic works, which is typical for a vehicle with a Throttle Position Sensor but no manifold pressure sensor, and an Oxygen sensor.

The calculations below happen continuously, thousands of times per second and are one of the the main functions of the ECU. All fueling calculations begin with an Open Loop calculation and proceed (under certain conditions) to the Closed Loop calculations.

Open Loop fueling calculations go roughly like this, performed on a millisecond by millisecond basis:
1) Read RPM and TPS: Find a base-fuel-value by using the four closest cells in the fuel table
2) Measure Engine Temperature: If not warmed-up, add a correction, otherwise skip this step
3) Measure Input Air Temperature (from the airbox IAT sensor): Apply a correction factor from a table
4) Measure Air Pressure (does the Magneti Marelli ECU have a built in sensor?): Apply a correction factor from a table
5) Measure Battery Voltage: Apply a correction factor from a table (corrects injector performance vs battery voltage)
6) Measure if TPS is moving, and how fast it is moving: add fuel if TPS opening, remove fuel if TPS closing.
7) Based on RPM/TPS: Apply Mixture Adaptation values (can be 2 or 3 or a small table) learned previously during Closed Loop
8) If the RPM or TPS is changing quickly, if the Throttle is open very wide, or if the engine is cold, fire injector for calculated time and go back to step 1, otherwise continue to step 8

Closed Loop fueling steps
9) Apply the most recent Lambda Control Factor (LCF) (short term fuel trim)
10) Read the O2 sensor and determine whether to increase or decrease the LCF so as to remain close to Lambda = 1 (or a shifted value)
11) Determine whether to update any Mixture Adaptation values (long term fuel trim)
11) Fire injector for calculated time and go back to step 1

The two yellow-highlighted steps are how the ECU learns and applies the corrections called Mixture Adaptations and how what is learned during the Closed Loop calculations gets applied to the Open Loop fueling calculations. It is elegant and powerful, and must be understood before making changes to a Closed Loop fueling system.

A key observation is that Open Loop and Closed Loop fueling are not separate processes. Closed Loop steps occur as often as possible so that the mixture stays as close to the O2 sensor switch point as possible, to keep the catalytic converter happy.

Type of Enhancements
1. Products that disconnect the O2 sensor and disable the ECU Closed Loop corrections: Powercommander and EJK. Both systems lengthen the fueling pulse after it leaves the ECU, on the way to the injectors. Usually an ECU goes into Limp Home Mode if the O2 sensor is disconnected, and the ECU can no longer calculate fuel trims.
2. Products that maintain closed loop but attempt to shift "open loop fueling", such as an IAT-shifter. In order to believe that these products work, you have to believe that there are no long term fuel trims.
3. Products that change oxygen sensor switching point lambda-shifters. Normally a narrowband O2 sensor switches between 200 and 800 mV exactly at lambda=1 (14.7:1 for gasoline). These products work by replacing the stock signal with one that switches between 200 and 800 mV at a richer lambda (e.g. Lambda=0.96, which is 13.8:1 for gasoline). The ECU then learns to add fuel in Closed Loop and create RICHER long term fuel trims. Examples of this type of product are the Innovate Motorsports LC-2 & MXT-L and the Nightrider AF-XIED.