If sudden early ignition (pre-ignition) occurs continuously in a short period of time, a DTC is stored. Pre-ignition is a phenomenon inherent to small displacement forced-induction engines. Atomized engine oil and detached deposits (carbon) can cause pre-ignition and promote engine knocking during low-speed, high-output operation. This is higher pressure knocking than normal knocking.
Pre-ignition is detected by the knock control sensor.
When pre-ignition occurs, the ECM limits output to suppress the pre-ignition. If pre-ignition occurs continuously, fuel cut may be performed in some situations, which may cause vehicle behavior similar to hesitation or shift shock. This is not a malfunction.
As pre-ignition cannot be detected if a knock control sensor malfunction occurs, the same fail-safe control occurs as for strong knock detection.
When this DTC is stored, the ECM enters fail-safe mode.
During fail-safe mode, the ECM limits the output.
Fail-safe mode continues until a pass condition is detected.
| DTC No. | Detection Item | DTC Detection Condition | MIL | Memory | Note |
|---|---|---|---|---|---|
| P137800 | Pre-ignition Detected | Continuous pre-ignition prevention fuel-cut control is performed twice (1 trip detection logic).
Continuous pre-ignition prevention fuel-cut control operation conditions: Sudden early ignition (pre-ignition) occurs 5 times or more continuously in a short period of time. |
Does not come on | DTC stored | SAE Code: P1378 |
| Trouble Area | |
|---|---|
| Ignition system | Ignition malfunction of ignition coil assembly or spark plug |
| Fuel injection system | Decrease in fuel injection volume |
| Lubrication system | ·
High oil consumption ·
Dilute / deteriorated oil ·
Additive |
| Fuel system | ·
Diesel fuel contamination ·
Addition of fuel additives ·
Fuel pump assembly ·
Low quality fuel |
| Engine related | Accumulated deposit (in combustion chamber) |
| Intake system | Air leaks |
| Exhaust system | Clogged exhaust system component |
As strong knocking due to pre-ignition may be caused by multiple superimposed factors, it is important to comprehensively investigate all possible causes.
The risk of this occurring is increased if driving up a steep incline while towing in a low gear, as low-speed, high-output operation occurs.
If the customer reports a knocking sound or drivability problems, check the value of Data List items "Consecutive Prevention Cylinder #1 History" through "Consecutive Prevention Cylinder #4 History".
If the distance traveled recorded in the Data List subtracted from the value of Distance for Control is equal to the customer reported mileage of the vehicle when control occurred subtracted from the current vehicle mileage, explain to the customer that this condition is due to normal control to prevent pre-ignition and not a malfunction.
Read Freeze Frame Data using the GTS. The ECM records vehicle and driving condition information as Freeze Frame Data the moment a DTC is stored. When troubleshooting, Freeze Frame Data can help determine if the vehicle was moving or stationary, if the engine was warmed up or not, if the air fuel ratio was lean or rich, and other data from the time the malfunction occurred.
Connect the GTS to the DLC3.
Turn the ignition switch to ON.
Turn the GTS on.
Enter the following menus: Powertrain / Engine / Trouble Codes.
Read the DTCs.
| Result | Proceed to |
|---|---|
| DTC P137800 is output | A |
| DTC P137800 and other DTCs are output | B |
If any DTCs other than P137800 are output, troubleshoot those DTCs first.
A
B
Connect the GTS to the DLC3.
Turn the ignition switch to ON.
Turn the GTS on.
Using the GTS, confirm the vehicle conditions recorded in the Freeze Frame Data which were present when the DTC was stored.
| Tester Display |
|---|
| Vehicle Speed |
| Engine Speed |
| Vehicle Load |
| Coolant Temperature |
| Short FT B1S1 |
| Long FT B1S1 |
| Fuel System Status Bank 1 |
| Misfire Count Cylinder #1 |
| Misfire Count Cylinder #2 |
| Misfire Count Cylinder #3 |
| Misfire Count Cylinder #4 |
Check the Freeze Frame Data sets recorded the moment the DTC was stored and after the DTC was stored.
Using the Freeze Frame Data, confirm the vehicle conditions when the DTC was stored, such as if the engine was idling with the shift lever in P, D or N or if the vehicle was being driven at a constant speed or accelerating.
| Proceed to |
|---|
| NEXT |
NEXT
Connect the GTS to the DLC3.
Start the engine.
Turn the GTS on.
Enter the following menus: Powertrain / Engine / Data List / Consecutive Prevention Cylinder #1 History 1 to Consecutive Prevention Cylinder #4 History 4 and Fuel Cut History 1 to Fuel Cut History 4
| Tester Display |
|---|
| Consecutive Prevention Cylinder #1 History 1 |
| Consecutive Prevention Cylinder #1 History 2 |
| Consecutive Prevention Cylinder #1 History 3 |
| Consecutive Prevention Cylinder #1 History 4 |
| Consecutive Prevention Cylinder #2 History 1 |
| Consecutive Prevention Cylinder #2 History 2 |
| Consecutive Prevention Cylinder #2 History 3 |
| Consecutive Prevention Cylinder #2 History 4 |
| Consecutive Prevention Cylinder #3 History 1 |
| Consecutive Prevention Cylinder #3 History 2 |
| Consecutive Prevention Cylinder #3 History 3 |
| Consecutive Prevention Cylinder #3 History 4 |
| Consecutive Prevention Cylinder #4 History 1 |
| Consecutive Prevention Cylinder #4 History 2 |
| Consecutive Prevention Cylinder #4 History 3 |
| Consecutive Prevention Cylinder #4 History 4 |
| Fuel Cut History 1 |
| Fuel Cut History 2 |
| Fuel Cut History 3 |
| Fuel Cut History 4 |
According to the Freeze Frame Data, attempt to reproduce the vehicle conditions that were present when the DTC was stored and read the Data List.
| Result | Proceed to |
|---|---|
| Values are displayed for multiple consecutive prevention cylinder histories of a specific cylinder | A |
| Values are displayed for multiple consecutive prevention cylinder histories of all cylinders | B |
If values are displayed for multiple consecutive prevention cylinder histories of a specific cylinder, check the value of Freeze Frame Data items Misfire Count Cylinder #1 through #4. If the misfire count of that cylinder is high, the cylinder is malfunctioning.
If the vehicle conditions when the DTC was stored cannot be reproduced, read the value of Freeze Frame Data items Misfire Count Cylinder #1 through #4 to determine if only a specific cylinder or all cylinders are malfunctioning.
A
B
Check the ignition system.
Interchange the ignition coil assembly and spark plug of the malfunctioning cylinder with those of a known good cylinder and according to the Freeze Frame Data, check if the malfunctioning cylinder returns to normal.
Read the Data List items Misfire Count Cylinder #1 to #4 while performing this procedure to determine which cylinder is malfunctioning.
| Result | Proceed to |
|---|---|
| The malfunctioning cylinder returns to normal | A |
| The malfunctioning cylinder does not return to normal | B |
A
B
Check the power source circuit, wire harness and connectors.
| Proceed to |
|---|
| NEXT |
NEXT
Connect the GTS to the DLC3.
Start the engine.
Turn the GTS on.
Enter the following menus: Powertrain / Engine / Data List / Short FT B1S1 and Long FT B1S1.
| Tester Display |
|---|
| Short FT B1S1 |
| Long FT B1S1 |
According to the Freeze Frame Data, attempt to reproduce the vehicle conditions that were present when the DTC was stored and read the Data List.
| Data List | Result | Proceed to |
|---|---|---|
| Short FT B1S1 + Long FT B1S1 | -15% or higher, or less than 15% | A |
| Other than above | B |
If the vehicle conditions when the DTC was stored cannot be reproduced, read the value of Freeze Frame Data items Short FT B1S1 and Long FT B1S1 to perform judgment.
"Total FT Bank 1" is used to detect an abnormal air fuel ratio. As the value of "Total FT Bank 1" is corrected by the ECM before it is displayed in the Data List, the displayed value may not be equal to the sum of the measured "Short FT B1S1" and "Long FT B1S1".
An abnormally lean or rich tendency can be checked by reading the following Data List items: A/F Learn Value Idle Bank 1, A/F Learn Value Low Bank 1, A/F Learn Value Mid No.1 Bank 1, A/F Learn Value Mid No.2 Bank 1 and A/F Learn Value High Bank 1.
The following may cause a lean air fuel ratio (an operating range in which the air fuel ratio learned value correction is +15% or more):
Decrease in fuel injector assembly injection volume
Decrease in mass air flow meter sub-assembly output (due to existence of foreign matter)
Air leaks in intake system after mass air flow meter sub-assembly
Decrease in fuel pressure (at fuel filter, fuel pump, fuel main valve assembly or fuel suction plate sub-assembly)
On vehicles which the learning value for each operating range can be checked, if the value of "A/F Learn Value High Bank 1" only is corrected to the positive side, a malfunction in the fuel system (clogging of the fuel pump or fuel filter) is suspected.
On vehicles which the learning value for each operating range can be checked, if the value of "A/F Learn Value Idle Bank 1" and "A/F Learn Value Low Bank 1" only is corrected to the positive side, an air leak after the mass air flow meter sub-assembly is suspected.
The following may cause a rich air fuel ratio (an operating range in which the air fuel ratio learned value correction is -15% or less):
Increase in the fuel injector assembly injection volume
Purge VSV system
A
B
Interview the customer for details about when oil maintenance was last performed and what brand of oil was used.
Check whether the specified engine oil grade was used and that engine oil additives were not used.
Perform an engine oil inspection (check the oil level and for dirt, etc.).
No problem with the engine oil.
Strong knocking due to pre-ignition may be due to ignition of atomized engine oil under certain conditions.
The risk of this occurring may be increased if the engine oil used is not the specified oil grade.
The risk of this occurring may be increased if engine oil additives have been used.
As strong knocking due to pre-ignition may be caused by multiple superimposed factors, even if the engine oil inspection result is NG, perform the following inspections after replacing the engine oil.
| Proceed to |
|---|
| NEXT |
NEXT
Interview the customer for details about what fuel they have used and smell the fuel to check for the following.
If the fuel smells like a mixture of gasoline and diesel fuel, etc..
If there is a possibility that diesel fuel may have be added by mistake.
If the malfunction started after refueling at an unfamiliar gas station.
If fuel additives have been used.
Even if any of the above conditions are met, if the engine is not malfunctioning, fill the fuel tank at a different gas station and check if the malfunction recurs.
| Result | Proceed to |
|---|---|
| None of the above conditions are met and the engine is not malfunctioning. | A |
| One or more of the above conditions are met and the engine is malfunctioning. | B |
Strong knocking due to pre-ignition may be caused by the type fuel used.
The risk of pre-ignition occurring may be increased depending on the ingredients of fuel additives used.
Even if no abnormalities are found in this inspection, if a malfunction occurs after the vehicle has been refueled, a problem with the fuel is suspected.
A
B
Check for accumulated deposits (carbon) and remove them. Deposits (carbon) may act as an ignition source if they become detached, leading to pre-ignition.
Strong knocking due to pre-ignition may be caused by detached deposits burning inside the cylinder.
| Proceed to |
|---|
| NEXT |
NEXT
Replace the fuel.
| Proceed to |
|---|
| NEXT |
NEXT
Connect the GTS to the DLC3.
Turn the ignition switch to ON.
Turn the GTS on.
Start the engine and warm it up until the engine coolant temperature 75°C (167°F) or higher with all the accessories switched off.
Enter the following menus: Powertrain / Engine / Data List / Engine Speed, Mass Air Flow Sensor and Coolant Temperature.
| Tester Display |
|---|
| Engine Speed |
| Mass Air Flow Sensor |
| Coolant Temperature |
According to the display on the GTS, read the Data List when the ignition switch to ON and while maintaining an engine speed of 3000 rpm.
| Result | Proceed to |
|---|---|
·
Idling (warmed up engine, without load): 1.0 to 3.0 gm/sec ·
Engine speed 3000 rpm (warmed up engine, without load): 4.0 to 14 gm/sec |
A |
| Other than above | B |
A
B
Connect the GTS to the DLC3.
Start the engine and warm it up until the engine coolant temperature reaches 75°C (167°F) or higher.
Turn the GTS on.
Warm up the air fuel ratio sensors at an engine speed of 2500 rpm for 90 seconds.
Enter the following menus: Powertrain / Engine / Active Test / Control the Injection Volume for A/F Sensor / Data List / Coolant Temperature, A/F (O2) Sensor Voltage B1S1 and A/F (O2) Sensor Current B1S2.
| Active Test Display |
|---|
| Control the Injection Volume for A/F Sensor |
| Data List Display |
|---|
| Coolant Temperature |
| A/F (O2) Sensor Voltage B1S1 |
| A/F (O2) Sensor Current B1S2 |
Monitor the output values of the air fuel ratio sensors (A/F (O2) Sensor Voltage B1S1 and A/F (O2) Sensor Current B1S2) displayed on the GTS.
The Control the Injection Volume for A/F Sensor operation lowers the fuel injection volume by 12.5% or increases the injection volume by 12.5%.
The air fuel ratio sensor (sensor 1) has an output delay of a few seconds and the air fuel ratio sensor (sensor 2) has a maximum output delay of approximately 20 seconds.
If the sensor output voltage does not change (almost no reaction) while performing the Active Test, the sensor may be malfunctioning.
| GTS Display (Sensor) | Injection Volume | Value |
|---|---|---|
| A/F (O2) Sensor Voltage B1S1
(Air fuel ratio sensor (sensor 1)) |
12.5% | Below 3.1 V |
| -12.5% | Higher than 3.4 V | |
| A/F (O2) Sensor Current B1S2
(Air fuel ratio sensor (sensor 2)) |
12.5% | Below -0.86 mA |
| -12.5% | More than 0.33 mA |
| Result | Proceed to |
|---|---|
| Output values are abnormal | A |
| Malfunction disappears when fuel injection volume is increased | B |
| Malfunction is still present when fuel injection volume is increased, even if output values are normal | C |
A
B
C
Replace the air fuel ratio sensor (sensor 1).
Perform "Inspection After Repair" after replacing the air fuel ratio sensor (sensor 1).
Replace the air fuel ratio sensor (sensor 2).
Perform "Inspection After Repair" after replacing the air fuel ratio sensor (sensor 2).
| Proceed to |
|---|
| NEXT |
NEXT
Replace the fuel injector assemblies of all cylinders.
Perform "Inspection After Repair" after replacing the fuel injector assembly.
| Proceed to |
|---|
| NEXT |
NEXT
Connect the GTS to the DLC3.
Turn the ignition switch to ON.
Turn the GTS on.
Enter the following menus: Powertrain / Engine / Active Test / Activate the Circuit Relay.
| Tester Display |
|---|
| Activate the Circuit Relay |
When performing the Active Test, check for an operating sound from the fuel pump (for low pressure side).
| Activate the Circuit Relay | Specified Condition |
|---|---|
| ON | Operating sound heard |
| OFF | Operating sound not heard |
| Proceed to |
|---|
| OK |
| NG |
OK
NG
Attach a fuel pressure gauge and check the fuel pressure when cranking the engine and after stopping the engine.
| Vehicle State | Specified Condition |
|---|---|
| Cranking engine | 196 to 588 kPa (2.0 to 6.0 kgf/cm2, 28 to 85 psi) |
| 5 minutes after stopping engine | 147 kPa (1.5 kgf/cm2, 21 psi) or higher |
If there is foreign matter such as iron particles on the fuel pump (for low pressure side), remove it.
Make sure that there are no leaks from the fuel lines, signs of fuel leakage or fuel odors.
If the air fuel ratio becomes lean only when the engine is running under a high load and at a high engine speed, clogging of the fuel filter is suspected.
| Proceed to |
|---|
| OK |
| NG |
OK
NG
Connect the GTS to the DLC3.
Start the engine and warm it up.
Turn the GTS on.
Enter the following menus: Powertrain / Engine / Data List / High Fuel Pressure Sensor.
| Tester Display |
|---|
| High Fuel Pressure Sensor |
Read the values.
| GTS Display | Condition | Specified Condition |
|---|---|---|
| High Fuel Pressure Sensor | ·
Shift lever position: P ·
A/C: Off ·
Engine warmed up ·
Engine idling |
2.4 to 30 MPa |
| Proceed to |
|---|
| OK |
| NG |
OK
NG
Inspect other related components.
If the malfunctioning part could not be determined by performing the preceding inspections, one of the following malfunctions is suspected.
Deposits in the intake manifold or on an intake valve
Delay in fuel supply due to adherence of the fuel to the deposits
| Proceed to |
|---|
| NEXT |
NEXT
Inspect the following fuel pump (for low pressure side) related parts:
Fuel pump (for low pressure side)
Fuel pressure regulator
Fuel lines and connecting parts
Fuel filter
| Proceed to |
|---|
| NEXT |
NEXT
Inspect the fuel pump control system.
| Proceed to |
|---|
| NEXT |
NEXT
Repair or replace the malfunctioning part.
Perform "Inspection After Repair" after repairing or replacing the malfunctioning part.
| Proceed to |
|---|
| NEXT |
NEXT
Check that the engine has returned to normal.
| Proceed to |
|---|
| NEXT |
NEXT
Connect the GTS to the DLC3.
Turn the ignition switch to ON.
Turn the GTS on.
Clear the DTCs.
| Proceed to |
|---|
| NEXT |
NEXT
Check for air leaks or blockage in the intake system components. If a connection problem or foreign matter is found, repair the connection or remove the foreign matter.
If there is foreign matter in the intake system components, remove it before proceeding to the next step.
If there is no foreign matter in the intake system components, check for foreign matter in the mass air flow meter sub-assembly. If there is foreign matter in the mass air flow meter sub-assembly, remove it.
| Proceed to |
|---|
| NEXT |
NEXT