Idle is high

[DarthKickass_imp]

Hello everyone. I joined last August when I got the bike. So far, it has been great. However, the last couple of days I have noticed that the idle is around 1600 rpm's. (2013 just over 10K miles). I've been reading around and I see that this is a fairly common problem but the answers I find are all over the place. I'm asking - does anyone have the solution?

[Django]

If I've got it right it boils down to: try to get a software update for the EFI from your Honda garage.

[Wisedrum]

The software update was the solultion for my 2013 CB and cured the idle problem. But it was in Germany. Is the new software available in rhe US? Guess no.. Honda did some faulty programming for the intake valves and corrected the mistales afterwards as the dealer told me.

Wisedrum

[DarthKickass_imp]

WOW, I would never had guessed a software problem. I wonder if the Honda shop near me is aware of it? I'll have to ask.
Thank you.

[Cormanus]

[url=http://cb1100forum.com/forum/showthread.php?tid=8120]This thread deals with a faulty IACV which seems a clear cause of high idling. There’s lots to wade through, but it is a solution that’s worked.

[Lord Popgun]

According to Honda of America, there is no software update.

So the US didn’t get one, some in Europe did.

[GoldOxide_imp]

WOW, I would never had guessed a software problem. I wonder if the Honda shop near me is aware of it? I'll have to ask.
Thank you.

RE software: A part of the reason why generally m/c's operate far more reliably and efficiently than ever before. Of course, software relies much on the health of the hardware sensors.

[SportsterDoc]

ECU program update has worked in Europe, where it is available.

The IACV is not an easy solution and should be the last resort.

FSM 5-16 covers DTC.

29-1 is IACV malfunction, listed as loose or poor connector contact or IACV or circuit malfunction. The symptom/failsafe mode is engine stalls, hard to start and rough idle. See FSM page 5-41 for details.

Since you only have a high idle, you may want to check the following:

TPS: Check wires at bend to connector, unplug and reconnect (key off), then do the TPS reset procedure and/or operate it unplugged to see if any difference. Failsafe value is 0 degrees.

EOT: Check wires near connector, unplug and reconnect. Failsafe value is 266 F, so even if EOT failed the ECM should not think oil to be cold, resulting in a fast idle.

IAT:According to the FSM, engine should operate normal, failsafe value is 95F, so the even if IAT failed the ECM should not think incoming air to be cold, resulting in a fast idle.

The FSM is not sufficiently complete on this issue, but there is a lot of info in the lengthy thread linked by Cormanus.
Code Retrieval

With ignition on or idling, sidestand down, the Malfunction Indicator light (MIL) / Check Engine Light (CEL) will blink a Diagnostic Trouble Code (DTC), if the code is active.
Long blink = 1.3 seconds is a 10 value
Short blink – 0.5 second is a 1 value
Example: 2 longs + 5 short = DTC 25 (does not distinguish between 25-1 or 25-2)

For a stored code, with engine off, under the left side cover, short brown and green wires in Data Link Connector (DLC). With ignition switch on and run/stop switch in run, read code after MIL illuminates once and goes off. If MIL stays on, there is no stored DTC.

The following test condensations are a collaboration by PopGun and SportsterDoc; exclude the use of Honda diagnostics tools, requiring only a multimeter (volts and ohms).

This is a work in progress. At this point, by not utilizing the Honda MCS (Motorcycle Communications System), resistance is available only for EOT and TP sensors. With additional research/input from fellow forum members, we intend to add data to this thread.

Meanwhile, if a code is active and the following tests provide in-spec values, it is likely that the sensor has failed/is failing.

DTC 1-1 MAP (Manifold Absolute Pressure) sensor low voltage or DTC 1-2 MAP (Manifold Absolute Pressure) sensor high voltage
With MAP connector disconnected, ignition switch on, stop/run on, probe connector outside pins black/yellow (+) to black/green (-) for 4.75 to 5.25 vdc.

If no voltage, with ignition off, check continuity on black/yellow to ECM connector.

With ignition off, check MAP output center pin light green/yellow wire for no continuity (infinity) to ground. For DTC 1-2, check for continuity to ECM connector.

DTC 2-1 MAP sensor hose connection
Check electrical connectors and manifold vacuum hose is intact/connected

DTC 7-1 EOT (Engine Oil Temperature) sensor low voltage
Measure resistance of sensor between terminals of 2.4 – 2.9 K ohms at 20 degrees C/68 degrees F.

With ignition switch off, sensor disconnected, check connector pin to red/blue wire for no continuity (infinity) to ground.

DTC 7-1 EOT sensor high voltage
With ignition switch off, sensor disconnected, check for continuity of red/blue and green/orange wires to ECM connector.

DTC 8-1 TP (Throttle Position) sensor low voltage
With ignition switch on and stop/run on, probe sensor contacts to verify steady voltage increase from throttle fully closed to throttle fully open.
With ignition switch off, disconnect the connector, then with ignition switch on and stop/run on, measure voltage between connector pins black/yellow (+) to black/green (-) for 4.75 to 5.25 vdc.

If no voltage, with ignition off, check continuity on black/yellow to ECM connector, for continuity of center pin sensor output black/red wire to ECM connector and for no continuity (infinity) of black/red wire to ground.

DTC 8-2 TP (Throttle Position) sensor high voltage
With ignition switch off, disconnect the connector, measure sensor resistance between black/red and black green of 0.5 to 1.5 K ohms. Then with ignition switch on and stop/run on, measure voltage between connector pins black/yellow (+) to black/green (-) for 4.75 to 5.25 vdc.

DTC 9-1 IAT (Incoming Air Temperature) sensor low voltage
With ignition switch off, disconnect the connector, check pin to green/blue wire for no continuity (infinity) to ground.

DTC 9-2 IAT (Incoming Air Temperature) sensor high voltage
With ignition switch off, disconnect the connector, check continuity of gray/blue and green/orange to ECM.
There are summaries in posts 651 and 975

http://cb1100forum.com/forum/showthread....light=IACV

http://cb1100forum.com/forum/showthread....#pid221630
Some issues have been "cured" by a prolonged higher speed run, which may burn off carbon build-up.

[GoldOxide_imp]

Tidy summary of Best Known Methods (BKMs) S.Doc.

I believe the Forum would agree when I say, "Thanks for doing that."

[SportsterDoc]

Thank you, but it was very much a team effort with Max.
pdedse also did a good summary in post 786
He sold his CB1100 then after the issue appeared to be solved, bought another!

http://cb1100forum.com/forum/showthread....#pid201424