Nissan Titan ECU Reset
I came across this info a couple of months ago while cruising the 350Z section of the Technosquare site. With the exception of the ECU reset procedure, all the other procedures here are available in the Titan service manual. The ECU reset procedure is invaluabe, as it allows almost instant reset of the ECU's RAM instead of the usual method of disconnecting the battery and guessing how long you must leave it disconnected.
I think it is important to do the learning procedures periodically, as it basically recalibrates the electro-mechanical positioners, namely the throttle valve positioner and the accelerator pedal positioners. After some use, these things get a little out of whack, and get kinda lost. This can cause problems like loss of power and idle issues. This method restores the proper min/max position voltages that the ECU sees from them.
I, personally, have seen the best improvement in my engine by doing the full procedure, starting with the ECU reset, followed by the other procedures. In fact, after doing this, I got back some of my low end grunt that was lost over the past months. I can actually catch a bit of rubber now, which I haven't been able to do for a long time! It also cured a slightly erratic idle I was having.
Give it a try, but be patient -- it may take a couple (or more) tries with your stopwatch to get it right -- timing is extremely important here!
Note: Make sure the engine is at operating temperature and all electrical loads are turned off prior to doing the idle air volume learning. Don't think it matters for an ECU reset.
From Technosquare website:
Please read all instructions and be familiar with them before any attempts.
ECU Resetting
Timing is extremely critical. If it is NOT DONE within the specifird time, the ECU will not reset and the Check Engine Light (CEL) will continue to remain ON. A stop watch or an analog clock with a second hand will be useful.
Operations Procedures:
1. Confirm that accelerator pedal is fully released, turn ignition switch "ON" and wait 3 seconds.
2. Repeat the following steps (2a and 2b) procedures quickly five times within 5 seconds.
2a. Fully depress the accelerator pedal (HARD).
2b. Fully release the accelerator pedal.
3. Wait 7 seconds, fully depress the accelerator pedal and hold for approx. 10 seconds until the CEL starts blinking.
4. Fully release the accelerator pedal (while the CEL is still blinking).
5. Wait 10 seconds.
6. Fully depress the accelerator pedal and hold for more than 10 seconds.
7. Fully release the accelerator pedal (The CEL light will continue to blink).
8. Turn ignition switch to "OFF" position and now you can start the car. The CEL light should be gone.
If the CEL light continues to remain ON, repeat the above steps. Timing is extremely critical for resetting the ECU.
Accelerator Pedal Release Position Learning
Operation Procedure:
1. Make sure that the accelerator pedal is fully released.
2. Turn ignition switch "ON" and wait at least 2 seconds.
3. Turn ignition switch "OFF" wait at least 10 seconds.
4. Turn ignition switch "ON" and wait at least 2 seconds.
5. Turn ignition switch "OFF" wait at least 10 seconds.
Throttle Valve Closed Position Learning
Operation Procedures:
1. Make sure that accelerator pedal is fully released.
2. Turn ignition switch is "ON."
3. Turn ignition switch is "OFF" wait at least 10 seconds.
Make sure that the throttle valve moves during above 10 seconds by confirming the operating sound.
Idle Air Volume Learning (Throttle Position Learning)
Operation Procedures:
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. Turn ignition switch "OFF" and wait at least 10 seconds.
5. Conform that accelerator pedal is fully released, turn ignition switch "ON" and wait 3 seconds.
6. Repeat the following (steps 7a, 7b) procedures quickly five times within 5 seconds.
7a. Fully depress the accelerator pedal (HARD)
7b. Fully release the accelerator pedal.
8. Wait 7 seconds, fully depress the accelerator pedal and hold for approx. 20 seconds until the Check Engine Light (CEL) stops blinking and turned ON.
9. Fully release the accelerator pedal within 3 seconds after the CEL is ON.
10. Start engine and let it idle.
11. Wait 20 seconds.
12. Rev up the engine two or three times and make sure the idle speed and ignition timing are within the specifications.