What are the Possible Causes of the DTC P0400 1998 Nissan Altima Sedan?
NOTE: The causes shown may not be a complete list of all potential problems, and it is possible that there may be other causes.
Exhaust Gas Recirculation (EGR) volume control valve stuck closed
Faulty Exhaust Gas Recirculation (EGR) volume control solenoid valve
Faulty EGR Valve
Faulty EGR temperature sensor and circuit
Exhaust Gas Recirculation (EGR) solenoid valve harness is open or shorted
Exhaust Gas Recirculation (EGR) solenoid valve circuit poor electrical connection
Dead (Weak) battery
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How to Fix the DTC P0400 1998 Nissan Altima Sedan?
Review the 'Possible Causes' mentioned above and visually examine the corresponding wiring harness and connectors. Ensure to check for any damaged components and inspect the connector pins for signs of being broken, bent, pushed out, or corroded.
The most likely cause of this problem is a clogged EGR valve or EGR flow passages. Before replacing any parts, try cleaning the EGR valve, tube, and passages with throttle body or carburetor cleaner. Also, check for damage or loose vacuum hoses to the EGR valve.
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What is the Cost to Diagnose the Code?
Labor: 1.0
To diagnose the P0400 1998 Nissan Altima Sedan code, it typically requires 1.0 hour of labor. The specific diagnosis time and labor rates at auto repair shops can differ based on factors such as the location, make and model of the vehicle, and even the engine type. It is common for most auto repair shops to charge between $75 and $150 per hour.
When is the Code Detected?
Exhaust Gas Recirculation (EGR) flow control is not responding
What are Code Possible Symptoms?
Engine Light ON (or Service Engine Soon Warning Light)
Engine hesitation
Code P0400 1998 Nissan Altima Sedan Description
Early Exhaust Gas Recirculation (EGR) systems component s include and EGR Valve, and Engine Control Μodule (ECΜ) Controlled Vacuum Switch Valve or EGR Solenoid and an EGR Vacuum Μodulator. Depending on the engine and driving conditions, the ECΜ will control the EGR Solenoid, which will operate the EGR Vacuum Μodulator to regulate the opening and closing of the EGR Valve.
P0400 1998 Nissan Altima Sedan Code - Exhaust Gas Recirculation Function No/Low Flow Detected
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