The issue I'm looking to get help on is the notorious high idle which is throwing the code P0507. I've read a bunch of forum posts and done the ECU/Idle relearn countless time and none seem to fix the problem.
Here's the procedure I'm following which was posted by a user called 04G35DPM in the G35driver forum.
After step 12 the car will idle around 700-600 but when I go to turn off the car and turn in back on; it will idle back up around 1000-900. Some things I should mention is that the car has a Injen CAI and (according to the PO) an Exedy stage 2 clutch. Also, when I go to turn off the car I step on the clutch to avoid a small rattle noise; the PO told me to do this. Could this be throwing off the idle back up? I've done the procedure turning off the car both ways; stepping on the clutch and simply switching the key off.4.) Idle Air Volume Learning
1. Perform EC-91, "Accelerator Pedal Released Position Learning" .
2. Perform EC-91, "Throttle Valve Closed Position Learning" .
3. Start engine and warm it up to normal operating temperature. Skip this if the engine is already warm as you might throw the code in idle.
4. Check that all items listed under the topic PREPARATION (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, turnignition switch ON and wait 3 seconds.
7. Repeat the following procedure quickly five times within 5 seconds. This interval must be 5 seconds before step 8 begins.
a. Fully depress the accelerator pedal.
b. Fully release the accelerator pedal.
8. Wait 7 seconds, fully depress the accelerator pedal and keep it for approx. 20 seconds until the MIL stops
blinking and turned ON.
9. Fully release the accelerator pedal within 3 seconds after the MIL turned ON.
9a. Perform step 10. within the above 3 seconds. The photo below shows the car in run after the 3 seconds. But, this never worked for me.
10. Start engine and let it idle.
11. Wait 20 seconds.
12. Rev up the engine two or three times and make sure that idle speed and ignition timing are within the
specifications.
13. Turn off the car and restart within/ before 10 seconds. (Better = 5 seconds) Now it should work. I think you have everything up til here, so try this last step.
This is where I'm looking for some help or advice; maybe I'm doing the process wrong. If not then I'm to the point of just taking it to a Nissan dealership and having them set the idle themselves. The thing holding me back is that the car also has a bad knock sensor harness (showing code P0327); will this be an issue if I was to take it a dealership?
Any help will be appreciated.