P0101
The computer sees an air measurement that doesn't match what's expected. The code doesn't confirm the sensor is damaged.
Mass or Volume Air Flow A Circuit Range/Performance.
Read the article for P0101Juan el Mecánico
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P0128
The engine did not reach the expected temperature under the controlled conditions. The cooling, measurement and conditions of use are still to be separated.
Coolant thermostat temperature below the control range.
Read the article for P0128P0171
The computer had to correct a mixture with more air or less fuel than expected at Bank 1.
System too lean, bank 1.
Read the article for P0171P0172
The computer detected a mixture with more fuel or less air than expected at Bank 1.
System too rich, bank 1.
Read the article for P0172P0201
The computer detected an electrical problem in the control circuit for injector 1. The code does not prove that the injector itself is faulty.
Injector circuit/open, cylinder 1.
Read the article for P0201P0202
The computer detected an electrical problem in the control circuit for injector 2. The code does not prove that the injector itself is faulty.
Injector circuit/open, cylinder 2.
Read the article for P0202P0203
The computer detected an electrical problem in the control circuit for injector 3. The code does not prove that the injector itself is faulty.
Injector circuit/open, cylinder 3.
Read the article for P0203P0204
The computer detected an electrical problem in the control circuit for injector 4. The code does not prove that the injector itself is faulty.
Injector circuit/open, cylinder 4.
Read the article for P0204P0300
The computer noticed irregular power inputs without limiting the condition to a single cylinder.
Random or multiple-cylinder misfire detected.
Read the article for P0300P0301
The computer detected that cylinder 1 was not contributing power consistently. It still does not know what caused that condition.
Cylinder 1 misfire detected.
Read the article for P0301P0302
The computer detected that cylinder 2 was not contributing power consistently. It still does not know what caused that condition.
Cylinder 2 misfire detected.
Read the article for P0302P0303
The computer detected that cylinder 3 was not contributing power consistently. The code does not identify which component caused the condition.
Combustion failure detected in cylinder 3.
Read the article for P0303P0304
The computer detected that cylinder 4 was not contributing power consistently. It still does not know what caused that condition.
Cylinder 4 misfire detected.
Read the article for P0304P0324
The computer detected that the system monitoring or controlling the detonation did not behave as expected.
Knock control system error.
Read the article for P0324P0327
The signal from the first detonation sensor on Bank 1 fell below the range the computer expected.
Knock sensor 1 circuit low input, bank 1.
Read the article for P0327P0340
The computer did not receive the expected signal to know the position of the levas tree. It doesn't confirm the sensor is the cause.
Camshaft position sensor A circuit fault, bank 1 or single sensor.
Read the article for P0340P0401
The computer expected more flow from the EGR system than it could verify.
Exhaust gas recirculation flow insufficient detected.
Read the article for P0401P0420
The computer calculated that the bank 1 catalyst system was performing below the expected threshold. This code alone does not justify replacing the catalytic converter.
Catalyst system efficiency below threshold, bank 1.
Read the article for P0420P0430
The computer calculated that the bank 2 catalyst system was performing below the expected threshold. This code alone does not justify replacing the catalytic converter.
Catalyst system efficiency below threshold, bank 2.
Read the article for P0430P0441
The computer detected that the movement of fuel vapours did not match what was expected during the purge.
Evaporative emission system incorrect purge flow.
Read the article for P0441P0442
The system detected a small seal loss in the fuel vapour-containing circuit.
Evaporative emission system small leak detected.
Read the article for P0442P0455
The system failed to maintain the expected sealing or flow to control fuel vapour.
Evaporative emission system gross leak or no flow detected.
Read the article for P0455P0456
The computer detected a very small seal loss in the fuel vapour system.
Evaporative emission system very small leak detected.
Read the article for P0456P0506
The engine revolutions at the slowdown were below the computer's target.
Idle control system RPM lower than expected.
Read the article for P0506P0507
The engine's downturns were above the computer's target.
Idle control system RPM higher than expected.
Read the article for P0507How this article was prepared
White Hat Mgmt LLC wrote this explanation from Juan el Mecánico’s structured diagnostic record and the cited sources. Automation only formats and translates reviewed content; it does not invent causes, parts, prices, or procedures.
Educational guidance only. It does not replace an inspection or service information for the exact vehicle.