5. Maintenance 

guide 

: 

Intake VVT Actuator can only be replaced as an assembly. Do not disassemble it and repair. 
Replacement of VVT actuator and Camshaft.   

727

2.12.7.16 DTC P0068 P0106 

1. DTC 

description: 

DTC P0068  Electronic Throttle Air Flow Error 

 

DTC P0106  Intake Pressure/Throttle Position Fault 

Intake Manifold Absolute Pressure (MAP) Sensor measures intake manifold pressure changes 
caused by the engine load, intake manifold vacuum and engine speed changes, and convert these 
changes into voltage output and send to the engine control module (ECM). At the same time the 
engine control module (ECM) compares the actual and expected intake manifold absolute pressure 
changes based on the throttle position opening change, to determine whether the intake manifold 
absolute pressure sensor responds to throttle position opening change or not. Set DTC P0106 fault 
accordingly. 

Engine control module (ECM) detects air flow based on the intake manifold pressure sensor and 
intake air temperature sensors measured data and compare the sir flow with expected air flow 
based on throttle position sensor. If the engine control module (ECM) detects that the intake 
manifold absolute pressure / temperature sensor detected actual air flow and expected air flow 
based on throttle position sensor is inconsistent, it will set DTC P0068. 

2.  Conditions For Setting DTC and The Fault Location: 

DTC Code

DTC Detection Strategy 

Conditions For Setting The 
DTC (Control Strategy) 

Fault Locations 

P0068 

Difference between intake 
manifold absolute pressure 
/ temperature sensor 
detected air flow and the 
expected air flow based on 
throttle position is 200 g/s. 

1. Engine 

Running 

2.  No Intake Air Pressure / 

Temperature Sensor Fault

3.  Duration Longer Than 4s.

P0106 

Atmosphere correction 
pressure value is more than 
high limit value. 

Or less than low limit value

1. Engine 

Running 

2.  No intake pressure sensor, 

coolant temperature 
sensor, ETC throttle 
position sensor, fuel 
injector, ignition coil and 
misfire fault, etc. 

3. Coolant temperature is 

higher than 60 (140 

℃

ºF)。 

4. Duration Longer Than 

15s. 

1. Intake 

manifold 
pressure 
/temperature 
Sensor 

2. Intake 

manifold and 
Vacuum Tube

3. Throttle 

valve 

4. ECM 

3. Diagnostic 

Steps: 

Note: Before carrying out this diagnosis step, observe the data list on fault diagnosis tester and 
analyze the accuracy of the data, as these will help with quick diagnosis. 

1 Initial 

Inspection 

Inspect if there are the following conditions: 

A.  Damaged Intake Manifold Pressure / Temperature Sensor Housing Is, Broken Vacuum Tubes 

728

B.  Damaged Intake Manifold Pressure / Temperature Sensor Seals 

C.  Intake Manifold Pressure / Temperature Sensor Loose or Improperly Installed 

D.  Throttle seals is damaged, causing air leaks. 

 

2 

Inspect whether there is control system DTC code other than DTC P0068 
P0106.

 

A.  Connect fault diagnosis tester to the vehicle diagnostic interface. 

B.  Rotated ignition switch to ON position    . 

C.  Press the power button of fault diagnosis tester. 

D.  Select the following menu items: Engine/Read DTC codes. 

E.  Read DTC codes. 

Results 

DTC Codes Shown 

To Step 

DTC P0068 P0106 

No 

DTC Code Other Than DTC P0068 P0106 

Yes 

 

3 

Inspect the atmospheric pressure parameter in the fault diagnosis data list. 

A)  Compare the atmospheric pressure parameter and the actual atmospheric pressure, refer to the 

"2.12.1.3 Relationship between Altitude and Atmospheric Pressure" in “Engine Control 
System”. 

Are the two similar? 

 

4 

Inspect the intake manifold pressure (MAP) sensor value with the engine 
running.

 

A. Start 

the 

engine. 

B.  When idling, observe the intake manifold pressure (MAP) sensor values. 

C.  During acceleration, observe the intake manifold pressure (MAP) sensor values. 

D.  Compare the above intake manifold pressure (MAP) sensor values. 

Are above intake manifold pressure (MAP) sensor values changed? 

No 

Replace the intake manifold pressure / 
temperature sensor. 

Yes 

Yes 

2.12.7.14 DTC Chapter Index 

Yes

Next 

729

 

5 

Inspect the intake manifold pressure sensor. 

A.  Shut down the engine. 

B.  Turn the ignition switch to ON. 

C.  Without disconnecting the intake manifold pressure sensor wiring harness connector, pull out 

the intake manifold pressure sensor from the intake manifold and use the vacuum pump. 
install the vacuum pump tube to the intake manifold pressure sensor. 

D.  Apply 50 kPa pressure on the intake manifold pressure sensor. Observe whether the intake 

manifold pressure (MAP) sensor value changes? 

 

6 

Inspect the intake manifold pressure sensor installation port and vacuum tubes. 

A.  Inspect the intake manifold pressure sensor installation port and vacuum tubes. 

Are the installation port and vacuum tubes blocked? 

 

7 

Inspect whether the intake manifold pressure sensor parameter responds to changes. 

A. Engine 

Running 

B.  After changed throttle valve. Stuck throttle valve, look at air intake manifold    pipe pressure 

sensor . 

Whether the sensor parameter value is rapidly changed according to the change of the position of 
the throttle. 

Does intake manifold pressure (MAP) sensor value rapidly change with the throttle position 
changes? 

 

8 

Inspect the intake manifold pressure sensor installation port and vacuum tubes. 

A.  Inspect the intake manifold pressure sensor installation port and vacuum tubes. 

Are the installation port and vacuum tubes blocked? 

 

Yes 

Clean and service the intake manifold 
and vacuum tubes. 

Replace the intake manifold pressure 
sensor. 

No 

Yes 

Go to step 9 

No 

Yes 

Clean and service the intake manifold 
and vacuum tubes. 

No 

Go to step 9 

No 

Replace the intake manifold pressure / 
temperature sensor. 

Yes 

Yes 

Go to step 7 

No

730