M8 problems
Road Captain
Joined: Apr 2007
Posts: 679
Likes: 120
From: Fairbanks, AK.
Yes but with the Rinehart slip-ons there's nothing that would stop a mouse from running to the cylinders through the exhaust system. The O2 sensor on the rear cylinder of the Heritage (and my Deluxe) is close to the head. Might be worth checking the header to head gasket seal and torque of the fasteners, plus the slip-on's seal.
Seasoned HDF Member
Joined: Dec 2005
Posts: 19,925
Likes: 8,027
From: poway
Yes but with the Rinehart slip-ons there's nothing that would stop a mouse from running to the cylinders through the exhaust system. The O2 sensor on the rear cylinder of the Heritage (and my Deluxe) is close to the head. Might be worth checking the header to head gasket seal and torque of the fasteners, plus the slip-on's seal.
Don't know of any mice that can chew through metal. (mighty mouse?)
The error is more than likely a loose connection. I guess a mouse could chew threw the wires.. :-(
Stage I
Joined: Jan 2018
Posts: 1
Likes: 0
From: Burbank, CA
Error Code- Check Engine Light
Hi All:
I'm looking for help from someone that doesn't have a vested interest. I have a 2017 Road King Special w/ Stage 4 kit, SEPST, S&S Muffler, and a dyno tune, all dealer installed with exception to the tune, but this was a guy that Harley recommended. I have over 3,000 miles on the bike and was on a ride recently when I got a check engine light. I checked oil, everything was fine, bike was running fine, no odd noises, so I rode home. I brought it to my local dealer the next day as everything should still be under warranty, and they told me the error code was a bad O2 sensor. They cleared the code and said they'd check it out. Long story short, they couldn't get the code to duplicate, and now they're saying the tuner was installed wrong. They want $150 to fix it. I called BS and said it's a Harley part installed by Harley and they need to fix it. They suggested I take it to where I bought it. Now the place I bought it has the bike and says they can't find anything wrong at all, including the tuner. They said they've put over 10 miles on the bike and there's no check engine light, no error code, everything runs fine and to come get the bike.
Soooooo.... my very long winded question is this.... Is it possible for Harley's to throw a false error code? Or am I getting screwed here? For the record, the original error code was P0134, which is the front 02 sensor.
Thanks in advance!
I'm looking for help from someone that doesn't have a vested interest. I have a 2017 Road King Special w/ Stage 4 kit, SEPST, S&S Muffler, and a dyno tune, all dealer installed with exception to the tune, but this was a guy that Harley recommended. I have over 3,000 miles on the bike and was on a ride recently when I got a check engine light. I checked oil, everything was fine, bike was running fine, no odd noises, so I rode home. I brought it to my local dealer the next day as everything should still be under warranty, and they told me the error code was a bad O2 sensor. They cleared the code and said they'd check it out. Long story short, they couldn't get the code to duplicate, and now they're saying the tuner was installed wrong. They want $150 to fix it. I called BS and said it's a Harley part installed by Harley and they need to fix it. They suggested I take it to where I bought it. Now the place I bought it has the bike and says they can't find anything wrong at all, including the tuner. They said they've put over 10 miles on the bike and there's no check engine light, no error code, everything runs fine and to come get the bike.
Soooooo.... my very long winded question is this.... Is it possible for Harley's to throw a false error code? Or am I getting screwed here? For the record, the original error code was P0134, which is the front 02 sensor.
Thanks in advance!
Seasoned HDF Member
Joined: Jan 2008
Posts: 13,674
Likes: 11,461
From: State of Confusion
Hi All:
I'm looking for help from someone that doesn't have a vested interest. I have a 2017 Road King Special w/ Stage 4 kit, SEPST, S&S Muffler, and a dyno tune, all dealer installed with exception to the tune, but this was a guy that Harley recommended. I have over 3,000 miles on the bike and was on a ride recently when I got a check engine light. I checked oil, everything was fine, bike was running fine, no odd noises, so I rode home. I brought it to my local dealer the next day as everything should still be under warranty, and they told me the error code was a bad O2 sensor. They cleared the code and said they'd check it out. Long story short, they couldn't get the code to duplicate, and now they're saying the tuner was installed wrong. They want $150 to fix it. I called BS and said it's a Harley part installed by Harley and they need to fix it. They suggested I take it to where I bought it. Now the place I bought it has the bike and says they can't find anything wrong at all, including the tuner. They said they've put over 10 miles on the bike and there's no check engine light, no error code, everything runs fine and to come get the bike.
Soooooo.... my very long winded question is this.... Is it possible for Harley's to throw a false error code? Or am I getting screwed here? For the record, the original error code was P0134, which is the front 02 sensor.
Thanks in advance!
I'm looking for help from someone that doesn't have a vested interest. I have a 2017 Road King Special w/ Stage 4 kit, SEPST, S&S Muffler, and a dyno tune, all dealer installed with exception to the tune, but this was a guy that Harley recommended. I have over 3,000 miles on the bike and was on a ride recently when I got a check engine light. I checked oil, everything was fine, bike was running fine, no odd noises, so I rode home. I brought it to my local dealer the next day as everything should still be under warranty, and they told me the error code was a bad O2 sensor. They cleared the code and said they'd check it out. Long story short, they couldn't get the code to duplicate, and now they're saying the tuner was installed wrong. They want $150 to fix it. I called BS and said it's a Harley part installed by Harley and they need to fix it. They suggested I take it to where I bought it. Now the place I bought it has the bike and says they can't find anything wrong at all, including the tuner. They said they've put over 10 miles on the bike and there's no check engine light, no error code, everything runs fine and to come get the bike.
Soooooo.... my very long winded question is this.... Is it possible for Harley's to throw a false error code? Or am I getting screwed here? For the record, the original error code was P0134, which is the front 02 sensor.
Thanks in advance!
Seasoned HDF Member
Joined: Apr 2015
Posts: 6,863
Likes: 3,727
From: St. Charles, MO
Hi All:
I'm looking for help from someone that doesn't have a vested interest. I have a 2017 Road King Special w/ Stage 4 kit, SEPST, S&S Muffler, and a dyno tune, all dealer installed with exception to the tune, but this was a guy that Harley recommended. I have over 3,000 miles on the bike and was on a ride recently when I got a check engine light. I checked oil, everything was fine, bike was running fine, no odd noises, so I rode home. I brought it to my local dealer the next day as everything should still be under warranty, and they told me the error code was a bad O2 sensor. They cleared the code and said they'd check it out. Long story short, they couldn't get the code to duplicate, and now they're saying the tuner was installed wrong. They want $150 to fix it. I called BS and said it's a Harley part installed by Harley and they need to fix it. They suggested I take it to where I bought it. Now the place I bought it has the bike and says they can't find anything wrong at all, including the tuner. They said they've put over 10 miles on the bike and there's no check engine light, no error code, everything runs fine and to come get the bike.
Soooooo.... my very long winded question is this.... Is it possible for Harley's to throw a false error code? Or am I getting screwed here? For the record, the original error code was P0134, which is the front 02 sensor.
Thanks in advance!
I'm looking for help from someone that doesn't have a vested interest. I have a 2017 Road King Special w/ Stage 4 kit, SEPST, S&S Muffler, and a dyno tune, all dealer installed with exception to the tune, but this was a guy that Harley recommended. I have over 3,000 miles on the bike and was on a ride recently when I got a check engine light. I checked oil, everything was fine, bike was running fine, no odd noises, so I rode home. I brought it to my local dealer the next day as everything should still be under warranty, and they told me the error code was a bad O2 sensor. They cleared the code and said they'd check it out. Long story short, they couldn't get the code to duplicate, and now they're saying the tuner was installed wrong. They want $150 to fix it. I called BS and said it's a Harley part installed by Harley and they need to fix it. They suggested I take it to where I bought it. Now the place I bought it has the bike and says they can't find anything wrong at all, including the tuner. They said they've put over 10 miles on the bike and there's no check engine light, no error code, everything runs fine and to come get the bike.
Soooooo.... my very long winded question is this.... Is it possible for Harley's to throw a false error code? Or am I getting screwed here? For the record, the original error code was P0134, which is the front 02 sensor.
Thanks in advance!
Cruiser
Joined: Aug 2017
Posts: 107
Likes: 13
From: New England
Maybe put the stock pipes back on, see if the CEL stops?
Stellar HDF Member
Joined: Sep 2009
Posts: 2,114
Likes: 666
Yes, any vehicle can, under the right conditions, log an “out of range” code for a sensor that either was disconnected while working on the bike and not reconnected before turning on the ignition switch, or the sensor itself may be intermittently bad causing an erroneous code.
OR
The engine is really running too lean in an area where the SEPST can not address due to emission regulations.
OR
The exhaust is causing reversion to the point where the o2 sensor(s) are seeing air and reporting excessively lean condition(s).
Based on the above if it were me I would wait to see if the code comes back.
If it does, I would not hesitate to take it to a tuner to get it fixed without a bunch of wasted time trying to diagnose a problem that can be diagnosed and addressed very quickly with the right tools and understanding.
Let us know what you do/find,
Bob
OR
The engine is really running too lean in an area where the SEPST can not address due to emission regulations.
OR
The exhaust is causing reversion to the point where the o2 sensor(s) are seeing air and reporting excessively lean condition(s).
Based on the above if it were me I would wait to see if the code comes back.
If it does, I would not hesitate to take it to a tuner to get it fixed without a bunch of wasted time trying to diagnose a problem that can be diagnosed and addressed very quickly with the right tools and understanding.
Let us know what you do/find,
Bob
Ultimate HDF Member
Joined: Jul 2014
Posts: 5,649
Likes: 430
From: MASS_hole
Ho does the general consensus with a good technical background feel about the voltage regulators being used on these m8 motors?
I my self have come to the understanding that when these don’t REGULATE well, wrong signals will be sent to the ECM
I my self have come to the understanding that when these don’t REGULATE well, wrong signals will be sent to the ECM
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Seasoned HDF Member
Joined: Dec 2005
Posts: 19,925
Likes: 8,027
From: poway
What signals? The left key switch thinks the ECM looks fat? The ECM get pissed off and throws a "I'm generally pissed off" code?
Ultimate HDF Member
Joined: Jul 2014
Posts: 5,649
Likes: 430
From: MASS_hole
You know what I mean max
my wife’s sporty had a bad voltage reg and it did **** off the ecm
engine lights and codes after codes
Maybe just a slightglitch and not a total mess. But just enough to thow false codes
my wife’s sporty had a bad voltage reg and it did **** off the ecm
engine lights and codes after codes
Maybe just a slightglitch and not a total mess. But just enough to thow false codes