Gunit

AI have a 350z HR 2007. I want to star by saying that I had this surging Revs (specially after the eng was warm, bouncing from 1500 to 2000 rpm) issue and got it fixed just by reseting it. No money spent. I'll tell you what happend to my case, but if you want the step by step how I fixed scroll down. My issue started when I cleaned my throttle body and MAF sensor at same time. Yes I did touched and pushed open the throttle blades by hand, car was off for about 5min or something (batt connected). Initially I tried the pedal dance multiple times even with a running clock by my side to match timing as best as possoble, but no luck. I also have acess to a Launch and a G scanner which I've tried to reset adaptation automatically and manually by following the steps provided but also didn't work. Then I tried removong throttle plugs to see if the fault log would cause the ecu to erase the maps and enable the relearn. No luck. An interesting function of Launch scanner was that I could increase the rpm manually, and I tried that as well and again, no luck. Long story short, here are the steps I took that worked for my case. I recomend reading everything before attempting: 1* with the key off the chamber, I disconnected + & - terminals from battery and joined both cables together, whilst I turned ignition on for about 1min to make sure it would fully drain any surface corrent. After that I reconnected batt and headed to bed, hoping for a better day. Next day I started and headed to work, revs were surging still. By the end of the day, with the car sitting for 10h, I decided to try re-learning it from cold before any crancking. I followed these steps. I did not use clock or anything, I just set my time counting pace based on how long 1 second takes, and I followed one step after another in the same order as shown, just as described. Step 2: Learning (this one I did like 3 times till I felt I got all steps correct) Timing is extremely critical. If it is NOT DONE within the specify time, the ECU will not reset and the Check Engine Light (CEL) will continue to remain ON. 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 keep it for approx. 10 seconds until the CEL starts blinking. 4. Fully release the accelerator pedal (while the CEL is still blinking) 5. Wait about 10 second. 6. Fully depress the accelerator pedal and keep it 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 to 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 to "ON". 3. Turn ignition switch to "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) It is better to count the time accurately with a clock. 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. Confirm that the accelerator pedal is fully released, then 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 keep it 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 (I kept eng runing ). After that my revs sat arround 1000 rpm but wasn't surging anymore! Then I remembered I had changed the idle speed on scanner before all that mess, so I've manage to re-set to the standard idle and then my warm idle sat on +- 650rpm. That moment was like winning the lottery, so I took it straight away for a 25km drive. And about 1 week later, I haven't had issues. Best of luck guys. Hope I helped someone.