Warm engine, RPM drops at startup, and then quickly goes to normal
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Warm engine, RPM drops at startup, and then quickly goes to normal
Hey all,
So I have another question related to my civic saga..
Got a diff engine in my civic (other thread explains my problems). Everything is running well, except I had to replace the upstream o2 sensor.
2005 honda civic
I think this issue has been happening since I got the car back.
On warm startup, the RPM will drop past the lowest notch mark (inbetween it and 0) and then quickly go back up to the idle mark (see picture).
It all happens in a couple seconds.
Idle does not waiver normally or when driving.
This only happens on startup sometimes (usually warm)
What could cause this?
Should I be worried?
How can I fix it?
Picture of idle RPM: (usually it sits right at the line. When I took this pic it was below it.
Thanks
So I have another question related to my civic saga..
Got a diff engine in my civic (other thread explains my problems). Everything is running well, except I had to replace the upstream o2 sensor.
2005 honda civic
I think this issue has been happening since I got the car back.
On warm startup, the RPM will drop past the lowest notch mark (inbetween it and 0) and then quickly go back up to the idle mark (see picture).
It all happens in a couple seconds.
Idle does not waiver normally or when driving.
This only happens on startup sometimes (usually warm)
What could cause this?
Should I be worried?
How can I fix it?
Picture of idle RPM: (usually it sits right at the line. When I took this pic it was below it.
Thanks
Last edited by thana; Jun 15, 2015 at 09:27 PM.
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Re: Warm engine, RPM drops at startup, and then quickly goes to normal
Idle RPM spec is 700 +/- 50 at operating temperature in park or neutral so that doesn't really look far off.
Try an idle relearn?
Try an idle relearn?
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