VQ40DE ENGINE: 5 things to do after replacing the ECM on the following Nissan Model.
You must perform this job after you replace the ENGINE CONTROL MODULE (Computer BOX) on Nissan Cars. This tutorial Suitable only to Nissan and Infiniti with engine code VQ40DE .
- 2001–2004- Nissan Pathfinder
- 2013–2016- Nissan Pathfinder
- 2001–2003- Infiniti QX4
- 2001–2004- Infiniti I35
- 2002–2018- Nissan Altima
- 2002–present- Nissan Maxima
- 2002–2006- Nissan 350Z
- 2002–2007- Infiniti G35 Coupe
- 2002–2006- Infiniti G35 Sedan
- 2002–2008- Infiniti FX35
- 2002–present- Nissan Murano (Z50)
- 2003–2016- Nissan Quest
- 2004–2008- Infiniti M35
- 2012–2013- Infiniti JX35
- 2013–2016- Infiniti QX60
When replacing ECM, the following procedure must be performed.
1.) Perform initialization of NVIS (NATS) system and registration of all NVIS (NATS) ignition key IDs.
2.) VIN Registration.
PERFORM:
DESCRIPTION VIN Registration is an operation to registering VIN in ECM. It must be performed each time ECM is replaced.
TOOLS: OBD Diagnostic Scanner like LAUNCH X431 PRO3
NOTE:
Accurate VIN which is registered in ECM may be required for Inspection & Maintenance (I/M).
- You need OBD Diagnostic Scanner to do thing Job.
3.) Accelerator Pedal Released Position Learning.
DESCRIPTION
Accelerator Pedal Released Position Learning is an operation to learn the fully released position of the accelerator pedal by monitoring the accelerator pedal posit ion sensor output signal. It must be performed each time harness connector of the accelerator pedal position sensor or ECM is disconnected.
TOOLS: No tools Required
OPERATION PROCEDURE
- Check that accelerator pedal is fully released.
- Turn ignition switch ON and wait at least 2 seconds.
- Turn ignition switch OFF and wait at least 10 seconds.
- Turn ignition switch ON and wait at least 2 seconds.
- Turn ignition switch OFF and wait at least 10 seconds.
4.) Throttle Valve Closed Position Learning.
DESCRIPTION
Throttle Valve Closed Position Learning is an operation to l earn the fully closed position of the throttle valve by monitoring the throttle position sensor output signal. It must be performed each time the harness connector of electric throttle control ac tuator or ECM is disconnected.
TOOLS: No Special tools required.
OPERATION PROCEDURE
- Check that accelerator pedal is fully released.
- Turn ignition switch ON.
- Turn ignition switch OFF and wait at least 10 seconds. Check that throttle valve moves during above 10 seconds by confirming the operating sound.
5.) Idle Air Volume Learning.
DESCRIPTION
Idle Air Volume Learning is an operation to learn the idle air volume that keeps each engine within the specific range. It must be performed under the following conditions:
- Each time electric throttle control actuator or ECM is replaced.
- Idle speed or ignition timing is out of specification
PREPARATION
Before performing Idle Air Volume Learning, check t hat all of the following conditions are satisfied. Learning will be cancelled if any of the following conditions are missed for even a moment.
- Battery voltage: More than 12.9 V (At idle)
- Engine coolant temperature: 70 – 100° C (158 – 212 ° F)
- PNP switch: ON
- Electric load switch: OFF (Air conditioner, headlamp, rear window defogger)
On vehicles equipped with daytime light systems, if the parking brake is applied before the engine is started the headlamp will not illuminate.
- • Steering wheel: Neutral (Straight-ahead position)
- • Vehicle speed: Stopped
- • Transmission: Warmed-up
Idle Air Volume Learning Without Computer OBD Tool
NOTE:
• It is better to count the ti me accurately with a clock.
• It is impossible to switch the di agnostic mode when an accelerator pedal position sensor circuit has a malfunction.
1. Perform Accelerator Pedal Released Position Learning.
2. Perform Throttle Valve Closed Position Learning.
3. Start engine and warm it up to normal operating temperature.
4. Check that all items listed under the topic PREP ARATION (previously mentioned) are in good order.
5. Turn ignition switch OFF and wait at least 10 seconds.
6. Confirm that accelerator pedal is fully released, then turn ignition switch ON and wait 3 seconds.
7. Repeat the following procedure quickly five times within 5 seconds.
a. Fully depress the accelerator pedal.
b. Fully release the accelerator pedal.
8. Wait 7 seconds, fully depress the accelerator pedal it for approx. 20 seconds until the MIL stops blinking and turns ON.
9. Fully release the accelerator pedal within 3 seconds after the MIL turns ON.
10. Start engine and let it idle.
11. Wait 20 Seconds.
12. Rev up the engine two or three times and check that idle speed and ignition timing are within the specifications.
13. If idle speed and ignition timing are not within the specification, Idle Air Volume Learning will not be carried out successfully. In this case, find the cause of the incident by referring to the DIAGNOSTIC PROCEDURE below.
DIAGNOSTIC PROCEDURE
If idle air volume learning cannot be performed successfully, proceed as follows:
1. Check that throttle valve is fully closed.
2. Check PCV valve operation.
3. Check that downstream of throttle valve is free from air leakage.
4. When the above three items check out OK, engine component parts and their installation condition are questionable. Check and eliminate the cause of the incident. It is useful to perform “TROUBLE DIAG NOSIS – SPECIFICATION VALUE”. Refer to EC-78 .
5. If any of the following conditions occur after the engine has started, eliminate the cause of the incident and perform Idle Air Volume Learning again:
• Engine stalls.
• Incorrect idle.
Idle Air Volume Learning With OBD Diagnostic Tool
