Intermittent Check Engine Light
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Road Master
Joined: Dec 2016
Posts: 855
Likes: 156
Intermittent Check Engine Light
2001 FXDX approx 44k miles.
Ive been getting a red check engine light when Im in higher RPMs 4200k and up. It is usually at higher speeds in 4th and 5th gear but it happened once in 3rd gear as well.
Usually its on for about 3 seconds then goes away. It usually disappears if I roll off the throttle. Additionally, I feel like theres been more vibrations in the floor boards.
I know it could be a million things, but any thoughts on obvious culprits that I should check? Thanks!
Ive been getting a red check engine light when Im in higher RPMs 4200k and up. It is usually at higher speeds in 4th and 5th gear but it happened once in 3rd gear as well.
Usually its on for about 3 seconds then goes away. It usually disappears if I roll off the throttle. Additionally, I feel like theres been more vibrations in the floor boards.
I know it could be a million things, but any thoughts on obvious culprits that I should check? Thanks!
Seasoned HDF Member
Joined: Jul 2008
Posts: 9,281
Likes: 1,139
From: southeast PA
Look at the both ends of each plug wire. Make sure that they are clean and making good contact. Inspect the insulation for signs of cracking. Check where the coil where the wires go into it.
While you're at it check the plugs.
You should also see if the bike threw any codes, since the CE light came on.
While you're at it check the plugs.
You should also see if the bike threw any codes, since the CE light came on.
Outstanding HDF Member
Joined: Mar 2015
Posts: 2,840
Likes: 900
From: Philly Suburbs
This may have nothing to do with your issue, but there was a time that my engine light came on intermittently, in much the same manner you described (2000 FXDX, so basically the same bike).
After my engine build everything seemed fine, until... I don't remember the exact sequence of events, but I was on a full day ride and my engine light started coming on here and there, at higher speeds. It would go out if I slowed down for a bit, IIRC. Shortly after, I detected an extremely annoying clicking sound from my cam chest. There's excruciating detail in this thread, but I'll cut to the chase so you don't need to read it:
https://www.hdforums.com/forum/dyna-...-sound-10.html
Basically, it turned out that my inner cam chain had developed a tight spot (or spots), possibly caused by a damaged tensioner. In short, it would bunch up ever so slightly at the point of greatest tension, then spring back to where it should be. I've named the phenomenon "Cam Apnea." Sort of like sleep apnea, except instead of your breathing stopping for a moment, the front cam would stop turning for a fraction of a moment, then spring forward to where it should be (I mean a REALLY brief interruption). Once I changed the cam chain, everything came back to normal and the light never reappeared. I'm not exactly sure of everything that can trigger that light on a carbed bike, but my theory was the Cam Position Sensor. I don't know why it didn't throw the light at lower speeds, but maybe the issue didn't fully present itself until engine speeds and/or temp was above a certain point...
Hopefully not your issue...
But here's my two cents with warning lights (TPMS on cars is a good example): When an annoying light comes on, we tend to look for all the reasons that may cause the light to come on without good cause... But sometimes the light is actually telling you something you should know, and is coming on exactly as intended.
Good luck!
After my engine build everything seemed fine, until... I don't remember the exact sequence of events, but I was on a full day ride and my engine light started coming on here and there, at higher speeds. It would go out if I slowed down for a bit, IIRC. Shortly after, I detected an extremely annoying clicking sound from my cam chest. There's excruciating detail in this thread, but I'll cut to the chase so you don't need to read it:
https://www.hdforums.com/forum/dyna-...-sound-10.html
Basically, it turned out that my inner cam chain had developed a tight spot (or spots), possibly caused by a damaged tensioner. In short, it would bunch up ever so slightly at the point of greatest tension, then spring back to where it should be. I've named the phenomenon "Cam Apnea." Sort of like sleep apnea, except instead of your breathing stopping for a moment, the front cam would stop turning for a fraction of a moment, then spring forward to where it should be (I mean a REALLY brief interruption). Once I changed the cam chain, everything came back to normal and the light never reappeared. I'm not exactly sure of everything that can trigger that light on a carbed bike, but my theory was the Cam Position Sensor. I don't know why it didn't throw the light at lower speeds, but maybe the issue didn't fully present itself until engine speeds and/or temp was above a certain point...
Hopefully not your issue...
But here's my two cents with warning lights (TPMS on cars is a good example): When an annoying light comes on, we tend to look for all the reasons that may cause the light to come on without good cause... But sometimes the light is actually telling you something you should know, and is coming on exactly as intended.
Good luck!
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Road Master
Joined: May 2015
Posts: 791
Likes: 221
From: sf bay area ca
if your check engine lite came on then back off u have a code stored in memory. check and see what it is
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Extreme HDF Member
Joined: Jun 2014
Posts: 11,448
Likes: 2,299
From: NW Ohio
The ECU in our old twinks are pretty crude.
Knowing they had recurring issues causing their ommision soon after debut, I'd'd suspect the cam position sensor. Not sure if '01 had them or not, tho.
Knowing they had recurring issues causing their ommision soon after debut, I'd'd suspect the cam position sensor. Not sure if '01 had them or not, tho.
Road Master
Joined: Aug 2008
Posts: 1,246
Likes: 251
From: Belle River Ontario
Start with the simple and go from there. Start with your charging system, check the battery, stator and regulator...including the battery cables. Inspect, clean and tighten if needed.
If all good check your plugs and plug wires. I would just change them anyway if they have not been done. Especially the wires. Most people ignore them but they do wear.
if after that is done and if it’s still a problem then look at the CPS etc.
If all good check your plugs and plug wires. I would just change them anyway if they have not been done. Especially the wires. Most people ignore them but they do wear.
if after that is done and if it’s still a problem then look at the CPS etc.