Error code p0101 & P0404 - 2001 Volkswagen Jetta TDI

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P1404 Code - What Does It Mean & How To Fix It

OBD2PROS https://obd2pros.com > Complete List of OBD2...
A P1404 code is not considered serious. The vehicle will run, but with decreased performance however, you should have it looked at right away. If the vehicle is ...

‎Meaning · ‎Common mistakes

P0404 OBD-II Trouble Code: Exhaust Gas Recirculation ...

YourMechanic https://www.yourmechanic.com > Articles
P0404 is a diagnostic trouble code (DTC) for "Exhaust Gas Recirculation Circuit Range/Performance". This can happen for multiple reasons and a mechanic ...

Error Code P0137: Oxygen Sensor Circuit Low Voltage B1S2

AutoZone https://www.autozone.com > diagnostic-trouble-codes
Specifically, the diagnostic trouble code P0137 yields the following message: "O2 Sensor Circuit Low Voltage (Bank 1, Sensor 2)." Here's what that means: Your ...

‎What Does the Code P0137... · ‎What Are the Symptoms of a...

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'Year make model' needed in all questions.

ABS and MAF are the codes. You need a good auto-electrician.

U1002: Code Meaning, Causes, Symptoms, & Tech Notes

https://www.engine-codes.com > u1002
The Diagnostic Trouble Code (DTC) sets when the Anti-Lock Brake System (ABS) Actuator and Electric Unit (Control Unit) is not transmitting or receiving ...

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  U1002 NISSAN - Engine-Codes.com

  https://www.engine-codes.com > u1002_nissan
  'What is U1002 NISSAN code meaning? ... The Diagnostic Trouble Code (DTC) sets when the Anti-Lock Brake System (ABS) Actuator and Electric Unit (Control Unit) is ...

P0101 What Does Code P0101 Mean? P0101 definition: Mass Air Flow (MAF) Circuit/Performance Malfunction. Issue Severity: MODERATE - Extended driving with this code can cause internal engine damage. Repair Urgency: Get this code fixed as soon as possible to avoid internal engine failure.Feb 21, 2022

P0101 - Meaning, Causes, Symptoms, & Fixes - FIXD

C1130 NISSAN Code Engine Signal 1 - AutoCodes

https://www.autocodes.com > c1130_nissan
Aug 17, 2018 - The code means that the Anti-Lock Brake System (ABS) control unit has detected that there is a problem with the Engine Control Module (ECM). ' .

Code 404 is for a problem with the EGR valve circuit.
The valve may be open or closed when it should not be.

both codes are for maf sensor is it plugged in

well it is a missfire the timing may be the issue here

P0101 is the Mass Air Flow Sensor error,
http://www.obd-codes.com/p0101


P0128 Coolant Thermostat (Coolant Temperature Below Thermostat Regulating Temperature

P0101 - Mass Air Flow (MAF) Sensor Performance

P1153 - Heated Oxygen Sensor (HO2S) Insufficient Switching Bank 2 Sensor 1

I would open the air intake hose and clean the mass air flow sensor with air pressure, but be carefull not to damage the small resistor.

P0404 IS EGR POSITION SENSOR PERFORMANCE..YOU NEED A NEW EGR VALVE..RECOMMEND DISCONNECTING BATTERY WHILE REPLACING EGR VALVE..SOMETIMES CODE WILL NOT GO AWAY EVEN AFTER REPLACING VALVE AND CLEARING CODE WITH SCANNER..VALVE IS LOCATED ABOVE ALTERNATOR ON END OF CYLINDER HEAD..THE BOTTOM BOLT CAN BE TRICKY TO REMOVE AND HAVE HAD TO REMOVE ALTERNATOR TO GET BOLT OUT..YOU WILL NEED A NEW GASKET FOR TUBE AS WELL..ABOUT 120 BUCKS FROM DEALER(CAN)

p0404 is egr flow range, remove and clean egr passage way, it maybe built up with carbon, p0101 remove and clean mass air flow sensor. you can buy the cleaner at any auto parts store. but be carefull of the inside of sensor, follow directions on can. this should help a lot!!