06-27-2017, 09:42 AM
Hello ALL CB owners,
.....idle speed fluctuation (when fully warmed up)....maybe this maybe that, dealer replaced few parts without any results.. :
(
If part is defective = needs replacement. If needs ECM/software reprogramming = YES must go for it.
But let's say your idle is erratic even if ALL components are NOT defective, ECU has the LATEST version, no DTC present, electrical connectors are sound, your bike has NO!!!! mickey-mouse ECU related aftermarket gizmos/modifications, throttle cables are not sticky and are adjusted properly as well as the th. plates, crankcase breather + other one are already cleaned out....what you MAY do next....
ISC or IACV does similar if not identical job in FI system= control idle (through air flow, not fuel) when throttle is closed .
Your throttle plate is closed and its voltage reading is being sent to ECU through TPS . ECU calculates its value ( and other values as well, like engine temperature , injection time, ignition timing.. etc) and continuously tells ISC/IACV to be open more or less to maintain proper idle .
I would check ( as ONE of possibilities) if throttle plate has excessive carbon build up, which prevents throttle plate to go to full closed position and as a result , TPS sends erratic signal to ECM which as a controller sends command to ISC/IACV to open-close-open....++++ and you get idle fluctuation.
In a less likely scenario ISC/IACV , intake valves may have carbon build up as well.
To check your throttle is not going to be so easy due to limited space access but it can be done...and make SURE you check your throttle body when plates are FULLY OPEN.
For my '13 CB with 42K, I regularly use fuel injection cleaner ( to gas tank) 2x a year when gas tank is full and oil /filter change due, drive my bike to empty tank and replace oil/filter = done.
For winter storage , I add FI cleaner (proper amount to fuel volume) when engine is still warm, idle it for a while, turn ignition off and park my bike for winter hibernation.
I always use highest octane rating available at the pump (usually 94 or 92)...'cuz it is LESS dirty than regular ( has less ppm)... I don't even know and care what octane rating owners manual recommends to use.
THIS IS WHAT I DO WITH MY LOVELY CB1100A... you may follow or not, it depends entirely up to you.
I do NOT intend to overwrite service manuals or provide field fix but only a THOUGHT.
All vehicles require regular maintenance as per manufacturer's manual = read yours, please.
Cheers to ALL
Peter
------------------
'13 CB, 42K
.....idle speed fluctuation (when fully warmed up)....maybe this maybe that, dealer replaced few parts without any results.. :
(If part is defective = needs replacement. If needs ECM/software reprogramming = YES must go for it.
But let's say your idle is erratic even if ALL components are NOT defective, ECU has the LATEST version, no DTC present, electrical connectors are sound, your bike has NO!!!! mickey-mouse ECU related aftermarket gizmos/modifications, throttle cables are not sticky and are adjusted properly as well as the th. plates, crankcase breather + other one are already cleaned out....what you MAY do next....
ISC or IACV does similar if not identical job in FI system= control idle (through air flow, not fuel) when throttle is closed .
Your throttle plate is closed and its voltage reading is being sent to ECU through TPS . ECU calculates its value ( and other values as well, like engine temperature , injection time, ignition timing.. etc) and continuously tells ISC/IACV to be open more or less to maintain proper idle .
I would check ( as ONE of possibilities) if throttle plate has excessive carbon build up, which prevents throttle plate to go to full closed position and as a result , TPS sends erratic signal to ECM which as a controller sends command to ISC/IACV to open-close-open....++++ and you get idle fluctuation.
In a less likely scenario ISC/IACV , intake valves may have carbon build up as well.
To check your throttle is not going to be so easy due to limited space access but it can be done...and make SURE you check your throttle body when plates are FULLY OPEN.
For my '13 CB with 42K, I regularly use fuel injection cleaner ( to gas tank) 2x a year when gas tank is full and oil /filter change due, drive my bike to empty tank and replace oil/filter = done.
For winter storage , I add FI cleaner (proper amount to fuel volume) when engine is still warm, idle it for a while, turn ignition off and park my bike for winter hibernation.
I always use highest octane rating available at the pump (usually 94 or 92)...'cuz it is LESS dirty than regular ( has less ppm)... I don't even know and care what octane rating owners manual recommends to use.
THIS IS WHAT I DO WITH MY LOVELY CB1100A... you may follow or not, it depends entirely up to you.
I do NOT intend to overwrite service manuals or provide field fix but only a THOUGHT.
All vehicles require regular maintenance as per manufacturer's manual = read yours, please.
Cheers to ALL
Peter
------------------
'13 CB, 42K