ECM test
Club Member
Joined: Feb 2007
Posts: 1,678
Likes: 3
First of all, why do you believe it is not healthy? It is very rare for an ECM to actually be the issue. Most of the time there is something else wrong when the bike is not running properly. For instance, bad spark plug wires, bad gas, holes in the gas line, exhaust leaks... I could go on and on, but I am sure you get my drift.
I know that this doesn't answer your question - the only thing I can think of is if you have a SERT or SEPST or TTS you could re-upload your calibration. If that worked then it is functioning as expected. Think of it like this, the ECM is like your computer. If you can start Windows (if the bike starts), then it is likely not the computer (not the ECM).
I know that this doesn't answer your question - the only thing I can think of is if you have a SERT or SEPST or TTS you could re-upload your calibration. If that worked then it is functioning as expected. Think of it like this, the ECM is like your computer. If you can start Windows (if the bike starts), then it is likely not the computer (not the ECM).
Thread Starter
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Intermediate
Joined: Jan 2010
Posts: 25
Likes: 0
From: Canada
I fried my power commander and when I removed it and plugged in just the ecm it ran really rough. I replaced the power commander and it got a little better but still it runs rough. I notice it most at a constant rpm as opposed to accellerating or decellerating. ?? any suggestions
Thread Starter
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Intermediate
Joined: Jan 2010
Posts: 25
Likes: 0
From: Canada
What you said makes sense. I think I was convinced it was the ecm mainly because I don't know enough about them. In truth if the bike was a carb then I would think it was a vacuum line by the way it runs.
I am willing to hear any suggestions
Thanks
I am willing to hear any suggestions
Thanks
Club Member
Joined: Feb 2007
Posts: 1,678
Likes: 3
Well here is a story that I have spun before...
My wife's 2003 heritage started running really rough, especially as it got hot. We took it into the shop and through their diagnostic processes they determined that they friend the Power Commander and ECM. They replaced the ECM and I bought a new Power Commander. They tuned it and it never ran quite right. I took it home and looked at the spark plug wires and found that there was a brown spot on the bottom of the one on the rear cylinder. These wires were aftermarket braided cables (covered in plastic). Apparently (somehow), they developed an arc against the engine and this would cause the bike to start to run bad. We put the old stock wires back on and the bike ran like it had prior to the issue.
Now why or how the dealer missed this I do not know. I have never been convinced that anything with the PC or the ECM was bad because the simple fix obviously was replacing the wires. If you talk to people such as FuelMoto, I would imagine they would tell you that the failure rate of the Power Commander is low (maybe you didn't fry it) and the ECM failure rate is probably even lower than that.
So..... If you have some aftermarket wires check those and you may want to see if you have pinholes in your fuel line inside your tank.
My wife's 2003 heritage started running really rough, especially as it got hot. We took it into the shop and through their diagnostic processes they determined that they friend the Power Commander and ECM. They replaced the ECM and I bought a new Power Commander. They tuned it and it never ran quite right. I took it home and looked at the spark plug wires and found that there was a brown spot on the bottom of the one on the rear cylinder. These wires were aftermarket braided cables (covered in plastic). Apparently (somehow), they developed an arc against the engine and this would cause the bike to start to run bad. We put the old stock wires back on and the bike ran like it had prior to the issue.
Now why or how the dealer missed this I do not know. I have never been convinced that anything with the PC or the ECM was bad because the simple fix obviously was replacing the wires. If you talk to people such as FuelMoto, I would imagine they would tell you that the failure rate of the Power Commander is low (maybe you didn't fry it) and the ECM failure rate is probably even lower than that.
So..... If you have some aftermarket wires check those and you may want to see if you have pinholes in your fuel line inside your tank.
Tourer
Joined: Jul 2006
Posts: 310
Likes: 23
From: Sykesville, MD
Does the bike run better with a full tank of fuel as oppossed to a half tank? If so, then you probably have holes in the Pump to Filter fuel hose inside of your tank. This is an easy inexpensive fix. Try filling your tank and see if it runs ok.
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Road Warrior
Joined: Apr 2009
Posts: 1,360
Likes: 4
Lots of things could be happening, perhaps the IAC is dirty. If it only ran rough without the PC it could be one or both O2 sensors. The PC disables the O2 Sensors and runs a bit rich. The richness could have made one or two of the O2 sensors lazy which could cause rough closed loop running.
I'm not familiar with the PC, but can you record or look at ECU sensor data with it, particularly O2 sensor voltage. I know any TTS and probably SESPT as well as the dealer can read these sensors and they may provide some insight. The tuners don't need to be married to a bike to simply read/record sensor data.
I'm not familiar with the PC, but can you record or look at ECU sensor data with it, particularly O2 sensor voltage. I know any TTS and probably SESPT as well as the dealer can read these sensors and they may provide some insight. The tuners don't need to be married to a bike to simply read/record sensor data.
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Club Member
Joined: Feb 2007
Posts: 1,678
Likes: 3
Lots of things could be happening, perhaps the IAC is dirty. If it only ran rough without the PC it could be one or both O2 sensors. The PC disables the O2 Sensors and runs a bit rich. The richness could have made one or two of the O2 sensors lazy which could cause rough closed loop running.
I'm not familiar with the PC, but can you record or look at ECU sensor data with it, particularly O2 sensor voltage. I know any TTS and probably SESPT as well as the dealer can read these sensors and they may provide some insight. The tuners don't need to be married to a bike to simply read/record sensor data.
I'm not familiar with the PC, but can you record or look at ECU sensor data with it, particularly O2 sensor voltage. I know any TTS and probably SESPT as well as the dealer can read these sensors and they may provide some insight. The tuners don't need to be married to a bike to simply read/record sensor data.
Club Member
Joined: Nov 2007
Posts: 4,474
Likes: 6
From: Port Charlotte, Florida
what bike are we talking about. My 07 dyna had alot of issues and they even replaced the ecm thinking it was that finally after some time it was traced down to a bare wire on the rear fuel injector that was shorting out to the frame causing it to cut in and out on the rear fuel injector and make it run like crap.