Engine RPM increases in neutral and idle

2009 HONDA ACCORD
102,000 MILES
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XJSHEN
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After throttle valve cleaning engine RPM level increased at idle to 1,000 RPM's and at neutral increased to 1,300 RPM's. How to fix the problem? The same cleaning on the Pontiac Montana was no problem and increased performance.
Sep 5, 2019 at 9:53 PM
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KENW1
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HI, is it the 2.4 or 3.5 engine?
Sep 7, 2019 at 8:21 AM
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KASEKENNY
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Hi,

How did you clean it?

More than likely the throttle position sensor is not reading properly. You will want to back probe the position sensor and see what the voltage is when the idle is high. You will want to see what both TPS A and B are when then is acting up. Also, see what the green wire is doing as well.

The PCM uses the throttle actuator to maintain correct idle speed and that is part of the TPS. If you cleaned the valve, it is possible that the TPS is no longer accurate which is causing the PCM to keep the idle high.

Let me know what you find and we can go from there. Thanks
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Sep 7, 2019 at 8:22 AM
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XJSHEN
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Your reply is helpless. What l need to know is How to Perform a Honda Accord Idle Learn Procedure like introduced in the YouTube. https://m.youtube.com/watch?v=-izuZvjCh4Q

PCM Idle Learn Procedure for Honda Accord
https://m.youtube.com/watch?v=K8VfHkMmeZA

Are these correct methods to resolve my problem?
Thanks for your reply and real help!
Sep 9, 2019 at 12:28 AM
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XJSHEN
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Is it possible to relearn idle procedure and resolve my problem using Honda HDS HIM diagnostic tool?
How to do that?
Thanks for your input and help?
Sep 9, 2019 at 12:39 AM
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KASEKENNY
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Sorry my response was of no help. Here is the procedure that you requested. The first is for a 2.4L and the second is for a 3.5L since we don't know which engine you have. They are the same except one has a step 6 and the other doesn't.

Please let us know how you make out. Thanks
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Sep 9, 2019 at 2:11 PM
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XJSHEN
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Fixed by reset TSP value using code reader instrument borrowed from a friend.
May 17, 2020 at 4:02 PM
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KASEKENNY
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Thanks for the update and glad you got it resolved.
May 17, 2020 at 7:13 PM
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