FREE REPAIR MANUALS & LABOR GUIDES 1982-2013 Vehicles
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P0301



P0301 00

Cylinder 1 Misfire Detected.







Fault symptom
Check Engine
(Check Engine lamp flashes if diagnostics has detected a misfire that is harmful to the catalytic converter).
Uneven running and misfiring.

On-board diagnosis

Type of diagnosis:
Continuous
Each misfire is registered and evaluated two different ways depending on the type of misfire.

Test 1
- Affects emissions.

Test 2
- Harmful to the catalytic converter.

Enable criteria:
General conditions for this DTC
- Positive engine torque (negative torque = engine breaking).
- Combustion signals from CDM are registered.

Test 1
- Number of combustions is registered.

Test 2
- The number of times no combustion signal is sent is tallied per cylinder every 200 engine revolutions. The total number of permissible misfires per 200 revolutions is indicated in a load and rpm-dependent matrix.

Fault criteria:
Test 1
- The number of times there was no combustion exceeds 3%.

Test 2
- The number of times there was no combustion exceeds the number of permissible misfires.

Dependent:
P1312, P1315, P1341, P1342, P1343, P1344

System reaction to a fault:
None

OK report:
OK-report takes place at ignition OFF if no fault report is generated during the driving cycle.

Fault handling:
Test 1
- Type II
- (See Description of On-Board Diagnostics/Fault handling II, "Emission-related misfiring or fault in fuel system" for more information.)

Test 2
- Type I
- (See Description of On-Board Diagnostics/Fault handling I, "Catalyst damaging misfiring" for more information).

Checking the wiring harness
Move the wiring harness at several spots and in several directions to reveal intermittent breaks and short circuits. Check switches, connectors and crimp connections for oxidation, retracted pins and pin clamping force.

Diagnostic help

Diagnosis regards:
System too rich, or too lean fuel/air-mix, bad compression, bad spark plugs causing imperfect combustion

Functions in the diagnostic tool related to the fault:
Test value:
- Misfire Cyl 1
- Airmass Deviation from Calculated
- Additive Adaptation
- Multiplicative Adaption

Activation:
- Reset Misfire Counters
- Injector 1
- Ignition coil 1
- Fuel Pump