ECM-4038 - Brake vacuum. Too low vacuum
System
Motorsteuergerät (ECM)
Volvo-Modelle, für die dieser Fehlercode gilt
Dieser Fehlercode hat je nach Modell, Modelljahr oder Motor unterschiedliche Bedeutungen. Wählen Sie die Bedeutung, die für Ihr Fahrzeug gilt.
Gilt für folgende Modelle:
5 ModelleC70 Cabriolet (1998–2005), C70 Coupé (1998–2002), S70 (1997–2000), S80 (1999–2006), V70 (1997–2000)
Modelle nach Baujahr und Motor anzeigen (8)
- Volvo C70 Cabriolet (1998–2005)2000Nur Motor: B5244S
- Volvo C70 Coupé (1998–2002)1999Nur Motor: B5254S DENSO
- Volvo C70 Coupé (1998–2002)2000Nur Motor: B5244S
- Volvo S70 (1997–2000)1999Nur Motor: B5252FS, B5254S DENSO
- Volvo S70 (1997–2000)2000Nur Motor: B5244S, B5244S2, B5244SG, B5244SG2
- Volvo S80 (1999–2006)1999–2000Nur Motor: B5244S, B5244S2
- Volvo V70 (1997–2000)1999Nur Motor: B5254S DENSO
- Volvo V70 (1997–2000)2000Nur Motor: B5244S, B5244S2, B5244SG, B5244SG2
Was bedeutet der Fehlercode?
The engine control module monitors that the engine can supply the brake booster with enough vacuum. The fault code is set when the difference between the intake manifold pressure and the air pressure around the car is too small while the airflow into the engine is too high. The code usually appears together with other fault codes that point to an airflow problem, and those should be checked first.
Mögliche Ursachen
- Air leak at the joint between the throttle body and the cylinder head
- Blocked, condensed or dirty lines running from the pressure sensor to the intake manifold
- Fault in the throttle unit or its throttle control
- Incorrect signal from the pressure sensor
Was Sie tun können
- 1Check other fault codes in the engine control module first, especially those for the throttle or airflow, since this code is often a result of them
- 2Make sure there is no air leak at the joint between the throttle body and the cylinder head
- 3Inspect the vacuum lines running from the pressure sensor to the intake manifold for blockage, condensation and dirt
- 4Have you got a diagnostic tool: compare the intake manifold pressure with the air pressure around the car at idle and check that they differ
- 5Switch off the ignition and wait until the throttle control module has shut down, then cycle the ignition and wait again before rechecking
- 6Have a workshop check whether the engine control module has the upgraded software from 2006 or later, and load it if it is missing
Symptome, die Sie bemerken können2
- Uneven idle
- Poorer performance at high speed
Was der Fehler beeinflussen kann3
- Cruise control is switched off during the operating cycle in which the fault was detected, and works again at the next start if the fault is gone
- Engine speed is controlled by cutting fuel to the cylinders one at a time, and the speed is limited
- The uneven idle may come from this reconfiguration rather than from a real drivability fault that existed before
Allgemeine Hinweise für Fahrzeughalter. Die Diagnose am Fahrzeug kann eine andere Ursache zeigen.