DESCRIPTION This DTC is stored if the combustion state of any cylinder is unstable.
Using
the Techstream, the conditions present when the DTC was stored can be
confirmed by referring to the freeze frame data. Freeze frame data
records engine conditions when a malfunction occurs. This information
can be useful when troubleshooting. It is
necessary to check if the vehicle ran out of fuel before performing
troubleshooting, as this DTC is also stored when idling is unstable due
to running out of fuel.
DTC No. | Detection Item |
DTC Detection Condition | MIL |
Memory | Note |
P160500 | Rough Idling |
When
idling with the accelerator pedal released and the vehicle stopped,
this item detects when the combustion is worsening at predetermined
levels from the changes in engine speed between the cylinders. Detection for 2 to 10 seconds according to the combustion state (1 trip detection logic). |
Does not come on | DTC stored |
SAE Code: P1605 |
Trouble Area | Ignition system |
- Spark plug
- Ignition coil assembly
| Fuel system |
- Fuel injector assembly (for port injection)
- Fuel injector assembly (for direct injection)
- Fuel pump (for low pressure side)
- Fuel pump assembly (for high pressure side)
- Fuel pump control circuit
- Fuel line
- Purge VSV system
- Fuel quality (existence of foreign matter, degradation)
| Intake and exhaust systems |
| Other control systems |
- ECM
- Wire harness or connector
- Knock control sensor
- Engine coolant temperature sensor
| Engine |
- Water inlet with thermostat sub-assembly
- Engine assembly
| High load from another system |
- Air conditioning system
- Power steering system
- Electrical load signal system
- A/T system
| CAUTION / NOTICE / HINT
HINT:
- DTC P160500
- FREEZE FRAME DATA
- Read freeze frame data using the Techstream. Freeze frame data records
engine conditions when a malfunction occurs. This information can be
useful when troubleshooting.
- When confirming the freeze frame data, be sure to check all multi freeze frame data.
Click here
- When confirming the freeze frame data, if there are multiple items
related to the cause of the malfunction, perform troubleshooting for all
related items.
- Try to operate the vehicle under the conditions recorded in the freeze
frame data which were present when the malfunction occurred. Confirm the
data at this time and the data when the engine is idling (engine warmed
up, no load, and shift lever in D or N) and compare this data with the
freeze frame data.
- PRECAUTIONS
- Inspections take into account the fact that the malfunction may not have
recurred and place emphasis on checking the vehicle conditions present
at the time when the malfunction occurred.
- When performing inspections, jiggle the relevant wire harnesses and
connectors in an attempt to reproduce malfunctions that do not always
occur.
PROCEDURE
1. | CHECK FOR ANY OTHER DTCS OUTPUT |
(a) Connect the Techstream to the DLC3. (b) Turn the engine switch on (IG).
(c) Turn the Techstream on. (d) Enter the following menus: Powertrain / Engine / Trouble Codes.
(e) Read the DTCs. Powertrain > Engine > Trouble Codes
Result | Proceed to |
Only DTC P160500 is output |
A | DTCs other than P160500 are output |
B |
HINT:
- If any DTCs other than P160500 are output, troubleshoot those DTCs first.
- Using freeze frame data, confirm the conditions the moment the DTC was
stored and after the DTC was stored. This information can be useful when
troubleshooting.
B |
| GO TO DTC CHART |
A |
| |
2. |
READ FREEZE FRAME DATA | (a) Connect the Techstream to the DLC3.
(b) Turn the engine switch on (IG). (c) Turn the Techstream on.
(d)
Using the Techstream, confirm the vehicle conditions recorded in the
freeze frame data which were present when the DTC was stored. Click here
Freeze Frame Data Item for DTC P160500 |
Suspected Area |
Action | Proceed to |
- Rough Idle Cylinder #1 to #6
- Plural Cylinders Rough Idle
| Compression Leakage Count |
"One of Rough Idle Cylinder #1 to #6 is ON" and "Plural Cylinders Rough Idle is OFF" |
4 or less |
- Spark plug
- Ignition coil assembly
- Fuel injector assembly (port or direct)
| Go to ROUGH IDLING (from step 7) |
A | Plural Cylinders Rough Idle is ON |
4 or less |
- Mass air flow meter sub-assembly
- Fuel injector assembly (port or direct)
- Fuel system (low or high pressure)
- Air fuel ratio sensor
| Go to ROUGH IDLING (from step 15) |
B | "One of Rough Idle Cylinder #1 to #6 are ON"
or "Plural Cylinders Rough Idle is ON" |
5 or more | Pressure loss from valve damage, deposits jamming the valve etc. |
Check compression and clean deposits in combustion chamber and intake system. |
C |
B |
| GO TO STEP 4 |
C |
| GO TO STEP 5 |
A |
| |
3. |
DETERMINE CAUSE OF MALFUNCTION FOR INDIVIDUAL CYLINDER |
(a)
Perform troubleshooting from Rough Idling step 7 (PERFORM ACTIVE TEST
USING TECHSTREAM (CHECK THE CYLINDER COMPRESSION) and onward. Click here
NEXT | |
GO TO ROUGH IDLING |
4. |
DETERMINE CAUSE OF MALFUNCTION FOR MULTIPLE OR ALL CYLINDERS |
(a) Perform troubleshooting from Rough Idling step 15 (READ VALUE USING TECHSTREAM (MASS AIR FLOW SENSOR)) and onward.
Click here
NEXT |
| GO TO ROUGH IDLING |
5. |
PERFORM ACTIVE TEST USING TECHSTREAM (CHECK THE CYLINDER COMPRESSION) |
(a) Warm up the engine. (b) Turn the engine switch off. (c) Connect the Techstream to the DLC3.
(d) Turn the engine switch on (IG). (e) Turn the Techstream on.
(f)
Enter the following menus: Powertrain / Engine / Active Test / Check
the Cylinder Compression / Data List / Compression / Engine Speed
Cylinder #1 to #6 and Average Engine Speed of All Cylinder. Powertrain > Engine > Active Test
Active Test Display |
Check the Cylinder Compression |
Data List Display |
Engine Speed Cylinder #1 |
Engine Speed Cylinder #2 |
Engine Speed Cylinder #3 |
Engine Speed Cylinder #4 |
Engine Speed Cylinder #5 |
Engine Speed Cylinder #6 |
Average Engine Speed of All Cylinder |
HINT: To display the entire Data List, press the pull down menu button next to Primary. Then select Compression.
(g) Push the snapshot button to turn the snapshot function on. HINT:
Using the snapshot function, data can be recorded during the Active Test.
(h) While the engine is not running, press the Active test button to change Check the Cylinder Compression to "Start".
HINT: After
performing the above procedure, Check the Cylinder Compression will
start. Fuel injection for all cylinders is prohibited and each cylinder
engine speed measurement enters standby mode. (i) Crank the engine for about 10 seconds.
(j)
Monitor the engine speed (Engine Speed Cylinder #1 to #6 and Average
Engine Speed of All Cylinder) displayed on the Techstream.
HINT:
- At first, the Techstream displays extremely high cylinder engine speed
values. After approximately 10 seconds of engine cranking, each cylinder
engine speed measurement will change to the actual engine speed.
- If the cylinder engine speed values (Engine Speed Cylinder #1 to #6)
displayed in the Data List do not change from an extremely high value,
return to the Active Test menu screen, change "Check the Cylinder
Compression" to "Start" and crank the engine again within 1 second.
NOTICE:
- Do not crank the engine continuously for 20 seconds or more.
- If it is necessary to crank the engine again after Check the Cylinder
Compression has been changed to "Start" and the engine has been cranked
once, press Exit to return to the Active Test menu screen. Then change
Check the Cylinder Compression to "Start" and crank the engine.
- Use a fully-charged battery.
(k) Stop cranking the engine, and then change "Check the Cylinder Compression" to "Stop" after the engine stops.
NOTICE:
- If the Active Test is changed to "Stop" while the engine is being cranked, the engine will start.
- When performing the Active Test, DTC P160400 (Startability Malfunction) may be stored.
- After performing the Active Test, make sure to check and clear DTCs.
(l) Push the snapshot button to turn the snapshot function off. (m) Select "Stored Data" on the Techstream screen, select the recorded data and display the data as a graph.
HINT: If the data is not displayed as a graph, the change of the values cannot be observed.
(n) Read the value.
HINT:
- If the value of Data List item "Engine Speed Cylinder #1 to #6" of a
cylinder is higher than other cylinders, the cylinder may be
malfunctioning.
- If the value of Data List item "Engine Speed Cylinder #1 to #6" is high for only one cylinder, compression loss is suspected.
Result | Proceed to |
There is no variation in "Engine Speed Cylinder #1 to #6" (All cylinders display approximately the same value for "Engine Speed Cylinder #1 to #6") |
A | There is variation in "Engine Speed Cylinder #1 to #6"
(Only one cylinder displays a value for "Engine Speed Cylinder #1 to #6" that differs considerably) |
B |
A |
| CLEAN OFF ANY DEPOSITS |
B |
| |
6. |
CHECK CYLINDER COMPRESSION PRESSURE | (a)
Measure the cylinder compression pressure. If the compression pressure
of a cylinder is low, inspect the engine assembly and repair or replace
parts as necessary. Click here
NEXT |
| END | |