Sudden Cut Out Low Speed

Ron Hudson

Site Supporter
Joined
May 3, 2020
Messages
23
Location
Union, KY
Bike
2010 Red NT700V..95PC800
Issue... Riding for an hour, 85 degrees, 60 mph.. all good, came into town, suddenly began bucking/jerking while shifting through stop signs
Then stalled out.. would start,then immediate cut out..felt like not enough fuel.. gave more throttle and started..had to maintain above 2500 rpms to keep running.. made to next location, shutdown for 30 min.. restarted, ran fine, continued last 20 miles of hilly areas shifting and lower speeds all normal.. Voltage steady at 14.0.. Would there be any Codes for this brief issue ? possible fuel sensor or air box sensor, just thinking.. Appreciate ideas.. Thanks
 
Start with the plug caps as previously stated. You might want to change out the spark plugs while you are there too.

If that does not solve the issue. Then you might want to start looking at the fuel pump assembly. The fuel filter is part of this assembly and cannot be replaced separately.
 
Because he states the problem got worse with stop and go traffic, where the engine is hottest, I'm going with crankshaft position sensor.
 
rc_heli_nut said:
Because he states the problem got worse with stop and go traffic, where the engine is hottest, I'm going with crankshaft position sensor.
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I disagree with you. I had an issue with that sensor. It would only fail after bike was shut off and when the part got heat-soaked while you were stopped to run an errand at a market or getting gas. Then the bike would not start and the ECU would throw a code. He has no code, so we are back to the plug caps.
 
If you do get an engine light, don't kill the key switch until you read the code. Pull over, put the bike in Neutral and put the kickstand down. The engine light will flash the active code(s) with a longer pause before repeating again.

You can read a code from memory, but that involves pulling the seat, and shorting the dummy load connector. A lot easier if you can catch it live before killing power to the bike.
 
My guess is that it is not the fuel pump as the OP said that it runs OK when >2500rpm. If it were the fuel pump losing pressure/volume it would seem that it would be more noticeable at higher RPMs. I'm gonna go with Heli-Nut and guess a crank sensor. Keep in mind Bruce that crank sensors can fail in a multitude of ways and not always display the same symptoms/mode of failure and if at this point it is an intermittent problem, not set the MIL.

Mike
 
When my fuel pump was dying, the symptoms I got occurred at higher rpm. If I was at 60 or above, opening the throttle felt like I had pulled a choke out. The mechanic donated some of his time during other jobs trying to find something other than a pump failure. I don't know what he tried but I do know he had it on the shop's dyno a couple of times. Finally he pulled the pump and did a pressure/flow check. The pressure check was nearly normal, but the flow was less than half of normal.
 
I would chill with assuming random parts are failing. That's not going to help OP. The service bulletin for the plug caps was trouble at idle in hot temps. See if they were changed out first.

If that isn't the fix, again I'm going to post this as people get way to excited to chuck parts at stuff. The very beginning of the Ignition chapter in the NT service manual states:

connections.PNG
 
NewTo700V said:
I would chill with assuming random parts are failing. That's not going to help OP. The service bulletin for the plug caps was trouble at idle in hot temps. See if they were changed out first.

If that isn't the fix, again I'm going to post this as people get way to excited to chuck parts at stuff. The very beginning of the Ignition chapter in the NT service manual states:

View attachment 17927
Click to expand...
Update Bike info... currently 8,000 miles purchased last year, put 2,000 on . I was aware of the Spark Plug Cap issue and have the Honda Bulletin.. dealer confirmed this was replaced.. so I took their word.. will check to see if NGK brand is installed. This is the first time any issues.. this does reflect more toward the Spark Plug Cap info .. makes sense to start with checking the connections.. to be clear, running fine at 60 mph came into town.. issue began as I hit several stop sign intersections, that is when the bucking lack of power hit.. always tried to start but immediately cut out.. giving more throttle at restart, could keep running if above 2500 rpm.. got to a safe spot, shut down for 30 mins, then restart all was fine.. thanks for all comments
 
Ron Hudson said:
got to a safe spot, shut down for 30 mins, then restart all was fine.. thanks for all comments
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This statement coincides how my bike was behaving before becoming more frequent. In the beginning it was very intermittent and it would throw a code during each instance briefly. The code clearly stated and pointed to the Crankshaft Positioning Sensor. However, both the issue and the code would go away and then the bike would fire up just fine when it had cooled for awhile.

So, I am willing to change my vote with additional information.
 
Ron Hudson said:
Update Bike info... currently 8,000 miles purchased last year, put 2,000 on . I was aware of the Spark Plug Cap issue and have the Honda Bulletin.. dealer confirmed this was replaced.. so I took their word.. will check to see if NGK brand is installed. This is the first time any issues.. this does reflect more toward the Spark Plug Cap info .. makes sense to start with checking the connections.. to be clear, running fine at 60 mph came into town.. issue began as I hit several stop sign intersections, that is when the bucking lack of power hit.. always tried to start but immediately cut out.. giving more throttle at restart, could keep running if above 2500 rpm.. got to a safe spot, shut down for 30 mins, then restart all was fine.. thanks for all comments
Click to expand...

I bought my NT two years ago with around 8,000 miles on the odometer. I was getting power loss at speed, eventually it happened enough to trigger engine light for throttle position sensor. Reading here and elsewhere seeing owners complaining of this, some having installed brand new throttle body assemblies, probably not needed. My experience with PGM-Fi issues on other Honda bikes has always been connection related. Plugs needed cleaning, failing fuse holders, oxidation etc. Components failing on such a low mileage bike seemed the last possibility to me. I pulled apart all connectors in the ECU to TPS path and cleaned them. Inspected wire condition into plugs. Pulled plug directly on the TPS, and plug between it and the ECU. There's a connector on the left side of the bike, clipped to the frame tube next to the airbox. It's a throttle body subharness, carries wiring for the TPS, CMP, MAP, and air intake control valve. Put back together and now close to 45K miles later it hasn't happened since.

If it were my bike, and plug caps were confirmed to have been upgraded but not having an active engine fault code to go on, I would track down a copy of the bike wiring schematic. Look at all the sensors in the ignition system on the schematic and all the plugs that live between them and the ECU. Find those sensors and plugs on the bike itself, unplug, clean with some Deoxit D5, plug and unplug connections a few times. Put everything back together and go ride,
 
You'll need the official Honda Service Manual to find the location of all the connector. They are in the General Info section which has pages and pages of excellent drawings showing the connections. You can buy the manual (used) from someone on this list or if you want a new copy, they are available from Helm & Associates in Detroit.

ps. I had a Crank Position Sensor fail while on a trip. It refused to restart after buying fuel on a hot day. Waiting 15-min allowed it to cool slightly and I got it restarted then it ran fine. Once home, I looked in the codes and found it identified the Crank Position Sensor as faulty so I replaced it.
 
NewTo700V said:
I would chill with assuming random parts are failing. That's not going to help OP. The service bulletin for the plug caps was trouble at idle in hot temps. See if they were changed out first.

If that isn't the fix, again I'm going to post this as people get way to excited to chuck parts at stuff. The very beginning of the Ignition chapter in the NT service manual states:

View attachment 17927
Click to expand...
Wise advice.
 
DirtFlier said:
You'll need the official Honda Service Manual to find the location of all the connector. They are in the General Info section which has pages and pages of excellent drawings showing the connections. You can buy the manual (used) from someone on this list or if you want a new copy, they are available from Helm & Associates in Detroit.

ps. I had a Crank Position Sensor fail while on a trip. It refused to restart after buying fuel on a hot day. Waiting 15-min allowed it to cool slightly and I got it restarted then it ran fine. Once home, I looked in the codes and found it identified the Crank Position Sensor as faulty so I replaced it.
Click to expand...
Was the MIL on Tosh?

Mike
 
Between Gillette and Spearfish this afternoon, the ambient air temperature was 100F and the bike was running fine at 80mph when I felt it start chugging. Before long it was bucking pretty hard at about 45. The engine temp was up to a little more than about half way between the half mark and the red area at the top. I ended up downshifting so that I was running a bit above 6,000 rpm in 3rd. I ran smooth like that and the engine temperature went down, but when I tried upshifting to 4th or 5th it went back to missing and the temp starting climbing again. After 2-3 miles at 60mph and 6,000 rpm, it smoothed out and ran fine the rest of the trip.

Any ideas??
 
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