MAP sensor
Thread Starter
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Cruiser
Joined: Aug 2012
Posts: 130
Likes: 26
From: West Michigan
MAP sensor
Hi-
2012 FLHTK 150,000 miles. Last ride it started to stumble. Over the course of about 5 miles of nursing it home it stumbled momentarily, then it seemed to run on one cylinder ok for a bit, then a couple of times engine quit completely while rolling, then would restart on it's own and run perfectly for a bit then repeat. Never backfired, just stumbled.
Fortunately I made it home, pulled codes from the odometer and it shows bad MAP sensor and a half dozen parts that I know it doesn't need, like a speedo and tach.
My questions are-
Does that engine behavior sound like a bad MAP sensor? ie is the code accurate?
Any point in trying to clean it, or should I just replace it?
My experience with carburetors and points is extensive, but the electronics throw me. Appreciate any input.
Thanks, guys.
2012 FLHTK 150,000 miles. Last ride it started to stumble. Over the course of about 5 miles of nursing it home it stumbled momentarily, then it seemed to run on one cylinder ok for a bit, then a couple of times engine quit completely while rolling, then would restart on it's own and run perfectly for a bit then repeat. Never backfired, just stumbled.
Fortunately I made it home, pulled codes from the odometer and it shows bad MAP sensor and a half dozen parts that I know it doesn't need, like a speedo and tach.
My questions are-
Does that engine behavior sound like a bad MAP sensor? ie is the code accurate?
Any point in trying to clean it, or should I just replace it?
My experience with carburetors and points is extensive, but the electronics throw me. Appreciate any input.
Thanks, guys.
Last edited by GlennJ; Nov 16, 2025 at 05:08 PM. Reason: Correct spelling error
Cruiser
Joined: Sep 2025
Posts: 167
Likes: 55
From: New England, Maine
Yes, that stumbling and cutting out is a classic symptom of a bad MAP sensor. The code is likely accurate.
Don't bother trying to clean it. Just replace the MAP sensor. It's a common failure point on high-mileage bikes.
The other codes are probably ghost codes caused by the main MAP sensor failure.
Don't bother trying to clean it. Just replace the MAP sensor. It's a common failure point on high-mileage bikes.
The other codes are probably ghost codes caused by the main MAP sensor failure.
Hi-
2012 FLHTK 150,000 miles. Last ride it started to stumble. Over the course of about 5 miles of nursing it home it stumbled momentarily, then it seemed to run on one cylinder ok for a bit, then a couple of times engine quit completely while rolling, then would restart on it's own and run perfectly for a bit then repeat. Never backfired, just stumbled.
Fortunately I made it home, pulled codes from the odometer and it shows bad MAP sensor and a half dozen parts that I know it doesn't need, like a speedo and tach.
My questions are-
Does that engine behavior sound like a bad MAP sensor? ie is the code accurate?
Any point in trying to clean it, or should I just replace it?
My experience with carburetors and points is extensive, but the electronics throw me. Appreciate any input.
Thanks, guys.
2012 FLHTK 150,000 miles. Last ride it started to stumble. Over the course of about 5 miles of nursing it home it stumbled momentarily, then it seemed to run on one cylinder ok for a bit, then a couple of times engine quit completely while rolling, then would restart on it's own and run perfectly for a bit then repeat. Never backfired, just stumbled.
Fortunately I made it home, pulled codes from the odometer and it shows bad MAP sensor and a half dozen parts that I know it doesn't need, like a speedo and tach.
My questions are-
Does that engine behavior sound like a bad MAP sensor? ie is the code accurate?
Any point in trying to clean it, or should I just replace it?
My experience with carburetors and points is extensive, but the electronics throw me. Appreciate any input.
Thanks, guys.
Thread Starter
|
Cruiser
Joined: Aug 2012
Posts: 130
Likes: 26
From: West Michigan
Yes, that stumbling and cutting out is a classic symptom of a bad MAP sensor. The code is likely accurate.
Don't bother trying to clean it. Just replace the MAP sensor. It's a common failure point on high-mileage bikes.
The other codes are probably ghost codes caused by the main MAP sensor failure.
Don't bother trying to clean it. Just replace the MAP sensor. It's a common failure point on high-mileage bikes.
The other codes are probably ghost codes caused by the main MAP sensor failure.
Thread Starter
|
Cruiser
Joined: Aug 2012
Posts: 130
Likes: 26
From: West Michigan
Got it. Thank you Sir!
Last edited by GlennJ; Nov 16, 2025 at 07:46 PM. Reason: Clarification
Cruiser
Joined: Apr 2021
Posts: 176
Likes: 43
From: New Port RicheyFL
Hi-
2012 FLHTK 150,000 miles. Last ride it started to stumble. Over the course of about 5 miles of nursing it home it stumbled momentarily, then it seemed to run on one cylinder ok for a bit, then a couple of times engine quit completely while rolling, then would restart on it's own and run perfectly for a bit then repeat. Never backfired, just stumbled.
Fortunately I made it home, pulled codes from the odometer and it shows bad MAP sensor and a half dozen parts that I know it doesn't need, like a speedo and tach.
My questions are-
Does that engine behavior sound like a bad MAP sensor? ie is the code accurate?
Any point in trying to clean it, or should I just replace it?
My experience with carburetors and points is extensive, but the electronics throw me. Appreciate any input.
Thanks, guys.
2012 FLHTK 150,000 miles. Last ride it started to stumble. Over the course of about 5 miles of nursing it home it stumbled momentarily, then it seemed to run on one cylinder ok for a bit, then a couple of times engine quit completely while rolling, then would restart on it's own and run perfectly for a bit then repeat. Never backfired, just stumbled.
Fortunately I made it home, pulled codes from the odometer and it shows bad MAP sensor and a half dozen parts that I know it doesn't need, like a speedo and tach.
My questions are-
Does that engine behavior sound like a bad MAP sensor? ie is the code accurate?
Any point in trying to clean it, or should I just replace it?
My experience with carburetors and points is extensive, but the electronics throw me. Appreciate any input.
Thanks, guys.
Thread Starter
|
Cruiser
Joined: Aug 2012
Posts: 130
Likes: 26
From: West Michigan
I've ordered a sensor, if it doesn't fix it then I've got a spare. In the meantime I'm going to inspect the peripheral stuff like wiring and connection integrity and anything else that comes up. Thanks.
Last edited by GlennJ; Nov 17, 2025 at 09:18 AM. Reason: Clarification
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Stellar HDF Member
Joined: Sep 2017
Posts: 2,144
Likes: 577
From: memphis
check for broken wires at the tmap sensor.
i had the same issue and i believe it was a broken ground wire at the plug. i just replaced the wires and all was well. if you wiggle those wires while the bike is running you may be able to get it to stall.
i had the same issue and i believe it was a broken ground wire at the plug. i just replaced the wires and all was well. if you wiggle those wires while the bike is running you may be able to get it to stall.
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Thread Starter
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Cruiser
Joined: Aug 2012
Posts: 130
Likes: 26
From: West Michigan
Planning on it. Thanks.
Seasoned HDF Member
Joined: Aug 2008
Posts: 5,071
Likes: 1,006
not necessarily
the obd2 system has an order of things and a failure in one area can trigger false codes.
it all depends upon HOW the map is used. map is a sensor that helps determine engine loading by diff'l pressures but it can also control things like transmission and such.
that is why proper diagnostics is needed before thrown parts and $$$$ till it runs.
it could be a skewed sensor, a leaking seal or hose (how it is hooked up) or a plugged hole (very tiny) that references atmospheric pressure.
your symptoms has a multitude of possible causes. i do not think dropping a cylinder is map based since map effects the whole engine. also, most ecu's have a fail safe that will allow the engine to run but with reduce power and such.
the obd2 system has an order of things and a failure in one area can trigger false codes.
it all depends upon HOW the map is used. map is a sensor that helps determine engine loading by diff'l pressures but it can also control things like transmission and such.
that is why proper diagnostics is needed before thrown parts and $$$$ till it runs.
it could be a skewed sensor, a leaking seal or hose (how it is hooked up) or a plugged hole (very tiny) that references atmospheric pressure.
your symptoms has a multitude of possible causes. i do not think dropping a cylinder is map based since map effects the whole engine. also, most ecu's have a fail safe that will allow the engine to run but with reduce power and such.
