Hallo Leute,
habe wieder ein Problem mit meinem Ranger Bj.98 3L V6. In niederen Drehzahlen und konstantem Gas geben habe ich ein "ruckeln" als wären es Zündaussetzer. Zündkerzen und Kabel sind ok. Motorkontrolleuchte ging an und es wurde ein Fehler des Abgasrückführventils festgestellt. Dieses habe ich jetzt getauscht aber das "ruckeln" in niedriegen Drehzahlen ist immer noch da. Weis von euch jemand eine Antwort???
..hat immer noch keiner von euch einen Tip????
Habe noch festgestellt wenn ich den Unterdruckschlauch abziehe läuft das Auto einwandfrei. Könnte das neue EGR-Ventil schon defekt geweseb sein???
LINCOLN-MERCURY:
1990-97 COUGAR
1991-99 CONTINENTAL, GRAND MARQUIS, SABLE, TOWN CAR, TRACER
1992-94 TOPAZ
1993-98 MARK VIII
1995-99 MYSTIQUE
LIGHT TRUCK:
1990 BRONCO II
1990-97 AEROSTAR
1990-99 RANGER
1991-99 EXPLORER
1994-96 BRONCO
1994-97 F SUPER DUTY, F-250 HD
1994-99 ECONOLINE, F-150, F-250 LD, F-350
1995-99 WINDSTAR
1997-99 EXPEDITION, MOUNTAINEER
1998-99 NAVIGATOR
1999 F-250 HD, SUPER DUTY F SERIES
SERVICE TIP
MASS AIR FLOW (MAF) DISCUSSION
MAF sensors can get contaminated from a variety of sources: dirt, oil, silicon, spider webs, potting compound from the sensor itself, etc. When a MAF sensor gets contaminated, it skews the transfer function such that the sensor over-estimates air flow at idle (causes the fuel system to go rich) and under-estimates air flow at high air flows (causes fuel system to go lean). This means Long Term Fuel Trims will learn lean (negative) corrections at idle and learn rich (positive) corrections at higher air flows.
If vehicle is driven at Wide Open Throttle (WOT) or high loads, the fuel system normally goes open loop rich to provide maximum power. If the MAF sensor is contaminated, the fuel system will actually be lean because of under-estimated air flow. During open loop fuel operation, the vehicle applies Long Term Fuel Trim corrections that have been learned during closed loop operation. These corrections are often lean corrections learned at lower air flows. This combination of under-estimated air flow and lean fuel trim corrections can result in spark knock/detonation and lack of power concerns at WOT and high loads.
One of the indicators for diagnosing this condition is barometric pressure. Barometric pressure (BARO) is inferred by the Powertrain Control Module (PCM) software at part throttle and WOT (there is no actual BARO sensor on MAF-equipped vehicles, except for the 3.8L Supercharged engine). At high air flows, a contaminated MAF sensor will under-estimate air flow coming into the engine, hence the PCM infers that the vehicle is operating at a higher altitude. The BARO reading is stored in Keep Alive Memory (KAM) after it is updated. Other indicators are Long Term Fuel Trim and MAF voltage at idle.
NOTE THE FOLLOWING PROCEDURE MAY ALSO BE USED TO DIAGNOSE VEHICLES THAT DO NOT HAVE FUEL SYSTEM/HO2S SENSOR DTCS.
Symptoms
^ Lack of Power
^ Spark Knock/Detonation
^ Buck/Jerk
^ Hesitation/Surge on Acceleration
^ Malfunction Indicator Lamp (MIL) Illuminated -
DTCs P0171, P0172, P0174, P0175 may be stored in memory
Vielleicht hilft das vorerst eoin bisschen weiter.
Machs halt wie alle: Kugel ausm Kugellager etc. in den Steuerschlauch und Ruhe is
Aber von mir hast Dus nicht
www.anncarina.de
Schaden.- und Wertgutachter spezialisiert auf US Ford.
Geht nicht? Gibt's nicht!
Bitte Anfragen nicht per Telefon stellen sondern nur übers Forum.
