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Old 08-09-2012, 11:26 AM   #47 (permalink)
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ecomodded's Avatar
Join Date: Jul 2011
Location: Vancouver Island, Canada
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Dusty - '98 VOLKSWAGEN Beetle TDI
90 day: 60.42 mpg (US)
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reb01501: Fuel cut-off during deceleration is of the adapted type. When the throttle is closed and the r.p.m. exceeds 1,700 (for engine speeds lower than 1,700 r.p.m., the cut-off function is not operative in order that an optimal drive-ability can be maintained) the injection of fuel is disactivated. If the supply is interrupted, the r.p.m. will start to fall more or less quickly in relation to vehicle conditions. Before reaching idle speed, the dynamics of the fall in r.p.m. is checked. If this exceeds a certain value, the fuel supply system is partially reactivated on the basis of a logic which envisages the "soft accompaniment" of the engine at idle speed. When this condition has been reached, the normal functions at idle speed are reactivated and cut-out during deceleration will only be reactivated if the fuel cut-off threshold is exceeded to prevent the engine from jerking. The reactivation thresholds for the fuel supply and cut-off vary in relation to engine temperature.
Another fuel cut-off logic has been developed within the control unit which intervenes during partial deceleration, ie. when a lower engine load is requested. The function is only activated if the new conditions last for a set period of time and after the ignition angle has been adapted to the new situation.

Reb, i can easily come off as slightly obnoxious myself at times,despite having no interest in being obnoxious.
Thanks for clarifying your intent.
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Last edited by ecomodded; 08-09-2012 at 11:37 AM..
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