Hunting rpm

[dave]

My bike has been exhibiting this hunting RPM for several months now. Sometimes too low, and stalling, and sometimes too high (about 1,500). The hunting went away for about two months, but the first time I rode it for an extended time around town with lots of stop & go, waiting for red lights, slow speeds and low RPM between stop lights, the low idle speed and stalling returned. Last weekend after it stalled the second time and I restarted it it suddenly went from idling too slow to idling too fast. Another member who visits this forum alerted us that the high speed idle on his bike was the result of a faulty Engine Oil Temperature (EOT) gauge. Two nights ago, when the high speed idle returned, I reached in with a gloved hand and pulled the wire off the EOT sensor. Magically the RPM returned to exactly 1,000 (it was at 1,500). The check engine light came on also. I turned the engine off, reconnected the EOT wire and restarted the engine and the high idle returned. So just yesterday I ordered an EOT sensor from my dealer. I have two questions: 1. I have proven a faulty EOT sensor will cause the idle speed to go high, but can it work both ways? 2. How can I test the new EOT sensor to ensure it is good before installing it?

Do you have service manual? The procedures are listed there.

Do you have service manual? The procedures are listed there. I own a Honda service manual, and the only thing I can find on the EOT sensor is on page 5-77, and all this is for the removal and installation. Can you point me to the page? Thanks.

Hey Dave,
Your EOT might not be faulty. The fault may occur when the oil reaches a certain temp and the ECU changes something, although why turning it off and on again helps, I'm not sure...
I've had this problem for a while and I've been assured that honda have sent a re-map to dealers to instal on bikes with this prob. It's only some years and models.

I haven't had it done yet, but might get it done this next week.
I'll report back how it goes. My bike does it most times I'm dawdling thru town with my girl on the back. I should be able to see if it has any effect fairly quickly...

Thank you for your feedback. I have seen posts in this forum where people claim a ECU change is available, and I have seen posts where people have been told by their dealer that a ECU change is not available. What year and model is your bike? Mike is a 2014 deluxe. Please post any news you have on tis subject. Thanks again.

To check the actual EOT sensor itself, turn the ignition off and remove the connector. On the sensor terminals measure the resistance.

From the manual: STANDARD: 2.4-2.9 Kohms (20degrees C/68 degrees F)

Thank you popgun. Did you find this in the Honda service manual? What page?

Hey Dave,
Your EOT might not be faulty. The fault may occur when the oil reaches a certain temp and the ECU changes something, although why turning it off and on again helps, I'm not sure...
I've had this problem for a while and I've been assured that honda have sent a re-map to dealers to instal on bikes with this prob. It's only some years and models.

I haven't had it done yet, but might get it done this next week.
I'll report back how it goes. My bike does it most times I'm dawdling thru town with my girl on the back. I should be able to see if it has any effect fairly quickly...

That's an interesting coincidence. The only time I have experienced the high idle / low idle - stalling is when riding around town, when I spend a lot of time waiting at stop lights. I thought maybe it was because the engine was getting hot, but the same thing has happened on a cool day (low 70's). Also, my wife is usually on the back when this happens.