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[cburch2]

All,

Need help.  I am trying to fix a false throttle input to the ECM.  A brief story below, read on if interested.

I just installed a Screaming Eagle Pro Tuner on my 07 CVO Softail Springer, 110 CI motor.  This was an attempt to fix three issues; deceleration pop, lean fuel mixture and RPM flux.

The bike is running great but the RPM flux is still present.  It is most noticeable at 2000 RPM, 2nd gear, 25 MPH and no throttle movement.  RPM will drop ~100 RPM, and the bike gives an audible decel sound.  It last but a short moment and returns to the previous RPM.  This event occurs randomly and a couple times a minute.

With the VCI of the tuner, I recorded engine performance.  I noticed with NO physical change of the throttle, the “throttle position indication” dropped 100 RPM and the engine would follow.  To me this meant the bike was receiving a false input?

Any thoughts, insights and comments are welcomed!

v/r,

Craig

[Fullsac Performance]

While the throttle blade may be stationary, the IAC (intake air control) may be actively moving. More likely just a lean surge.
Take it out of closed loop and ad a touch of fuel in the problem area for a test if you don't have a source of real time AFR info.

SG

[cburch2]

SG,

Thanks for the info. 

Still new to the tuner details and the closed loop options.  I will look at the instruction manual to see what it says. 

I have incresed the fuel mixture and wanted to run it a bit and then recheck the plugs. 

[glens]

With the VCI of the tuner, I recorded engine performance.  I noticed with NO physical change of the throttle, the “throttle position indication” dropped 100 RPM and the engine would follow.  To me this meant the bike was receiving a false input?

Absolutely.  You've got either a problem in the wiring/connectors between the TPS and the ECM or a fault in either of them.  It's not unheard-of to have a TPS develop intermittent operation.  Ever have a stereo where you'd get crackle out of the speakers any time you touched one of the bass/treble/balance/volume knobs?  Pretty much the same thing can happen with the TPS, which is essentially a rotary "volume" control.

[cburch2]

SG,

Looked up the "closed loop" paragraph.

Tuning with Closed-Loop

If a large part of the original calibration’s AFR table reads 14.6 AFR (the numbers in the cells will be in bold font) then that calibration is indeed closed loop.

The AFR table controls the operating conditions in which the ECM will enable closed-loop. The AFR cell must equal 14.6 for the ECM to enable closed-loop operation. This allows the user to control if and when the bike is in closed-loop using the AFR table.

I did note in the MAP I am editing that some of my AFR is still in the closed loop area.

I will fix that tonight and give her a ride in the morning.

**********************************************************
Glens,

Good point.  Hope the AFR fixes it.  I am not much of a spark chaser.

Wish me luck,

Craig

[Fullsac Performance]

Absolutely.  You've got either a problem in the wiring/connectors between the TPS and the ECM or a fault in either of them. It's not unheard-of to have a TPS develop intermittent operation.  Ever have a stereo where you'd get crackle out of the speakers any time you touched one of the bass/treble/balance/volume knobs?  Pretty much the same thing can happen with the TPS, which is essentially a rotary "volume" control.

True, but His bike is not FBW. He's controlling the butterfly manually. An intermittant TPS signal wont make the butterfly move or float. He didn't mention any codes?
The ECM will toss a code pretty quick with any intermittent signal from the TPS. Leave one unplugged by mistake and watch how fast it happens. Lol..
I'm kinda thinking its a tuning issue, I could be wrong.

SG

[Fullsac Performance]

SG,

Looked up the "closed loop" paragraph.

Tuning with Closed-Loop

If a large part of the original calibration’s AFR table reads 14.6 AFR (the numbers in the cells will be in bold font) then that calibration is indeed closed loop.

The AFR table controls the operating conditions in which the ECM will enable closed-loop. The AFR cell must equal 14.6 for the ECM to enable closed-loop operation. This allows the user to control if and when the bike is in closed-loop using the AFR table.

I did note in the MAP I am editing that some of my AFR is still in the closed loop area.

I will fix that tonight and give her a ride in the morning.

**********************************************************
Glens,

Good point.  Hope the AFR fixes it.  I am not much of a spark chaser.

Wish me luck,

Craig

For a quick test, change the target AFR from 14.6 to 13.0 from idle to 2500 RPM. Its a big change,if the problem disappears, you were lean. If it changes nothing,
you can start scratching your head in a different place. With out real time AFR info, your going to have to shoot in the dark a little.

SG

SG

[cburch2]

SG,

Thanks,

My values on the AFR I edited last night are all in the 13.9 range and lower.  Going to upload this tune in the AM and give her a ride to work.  I will go lower if the RPM flux persists.

Craig

[glens]

I am trying to fix a false throttle input to the ECM.

The ECM is getting false indication that the butterfly has moved, when it indeed has not moved, correct?

I just installed a Screaming Eagle Pro Tuner ... [in] an attempt to fix ... lean fuel mixture and RPM flux.

This RPM flux is likely cause by an incorrect fuel mixture (and maybe spark timing) because the ECM thinks the throttle plate has changed position when in fact it has not.

The ... RPM flux is still present.  It is most noticeable at 2000 RPM, 2nd gear, 25 MPH and no throttle movement.  RPM will drop ~100 RPM, and the bike gives an audible decel sound.  It last but a short moment and returns to the previous RPM.  This event occurs randomly and a couple times a minute.

Assuming for the moment that the coils, injectors, and fuel pump are not themselves experiencing intermittent operation, an audible decel sound could very well be indicative of at least the deceleration enleanment kicking in because the ECM thought you'd decelerated by closing the throttle at least some.

With the VCI of the tuner, I recorded ... [and] noticed with NO physical change of the throttle, the “throttle position indication” dropped 100 RPM and the engine would follow.  To me this meant the bike was receiving a false input?

The TPS does not indicate in a value of "RPM".  I'm assuming you mean the TPS indication drops in both percentage value and in volts, whichever scale you're using.

I'd say there is a common factor so far in every one of these declarations/descriptions you've given, and they all lead me to believe that the ECM is incorrectly thinking you've decreased throttle position at times when your cable-driven butterfly has in fact not budged.  Am I correctly understanding that specific point?

If so, then I'd say you now know exactly where to look.  If it's an electrical problem you will not succeed in trying to cover it up by altering any portion of your tune.  You really need to eliminate all possible or actual electrical anomalies before proceeding with altering the calibration.  Since you aren't "much of a spark chaser" the simplest thing for you to do would be to carefully break then re-make all connections between the TPS and ECM.  If the problem persists, somehow obtain a known-good TPS and replace the one on your bike with it to see if you can replicate the problem.  If the problem continues, then it's got to be either in the ECM or the wiring between the TPS and ECM.

While I or any of several thousand other people could troubleshoot this for you in a beer or two's time, I'm reluctant to try to hold your hand on a walk-through of the process over the Internet.  Do you have an analog voltmeter at your disposal and do you feel comfortable that you can use it without physically damaging connector components while probing them?  If not, then there's absolutely no shame in getting the bike and someone who can competently diagnose electrical issues in the same room.

How about attaching your recorded datalog file here so I/we can have a look-see?

[glens]

His bike is not FBW. He's controlling the butterfly manually. An intermittant TPS signal wont make the butterfly move or float.

I understood him to be specifically stating that the TPS signal indicated cable-driven butterfly movement when in fact there had been none.

He didn't mention any codes?  The ECM will toss a code pretty quick with any intermittent signal from the TPS. Leave one unplugged by mistake and watch how fast it happens. Lol..

He hasn't mentioned any codes.  I don't think a somewhat-flaky TPS will necessarily through codes.  If the wiper isn't reliably contacting the resistive trace or coil (whatever the internal design) at all times, it can behave exactly as he's portrayed thus far.  In this case the symptom could appear all the same with a less-than-perfect harness connection.

I'm kinda thinking its a tuning issue, I could be wrong.

It's certainly possible, but that tuning issue may be a result and not a cause.  We really need to be able to concretely determine the root of the problem to get to the solution in the shortest amount of time.

[low and slow]

Quote from: cburch2 on Yesterday at 10:27:49 PM
I am trying to fix a false throttle input to the ECM.

The ECM is getting false indication that the butterfly has moved, when it indeed has not moved, correct?

Correct.  I do not have a FBW throttle.  I noticed the throttle position indication indicated a move on the recorded data and the engine responded in kind.

Quote
I just installed a Screaming Eagle Pro Tuner ... [in] an attempt to fix ... lean fuel mixture and RPM flux.

This RPM flux is likely cause by an incorrect fuel mixture (and maybe spark timing) because the ECM thinks the throttle plate has changed position when in fact it has not.

Added fuel, ran the bike and the flux almost completely disappeared.  It fluxed just once or twice.  Could be onto something!

Quote
The ... RPM flux is still present.  It is most noticeable at 2000 RPM, 2nd gear, 25 MPH and no throttle movement.  RPM will drop ~100 RPM, and the bike gives an audible decel sound.  It last but a short moment and returns to the previous RPM.  This event occurs randomly and a couple times a minute.

Assuming for the moment that the coils, injectors, and fuel pump are not themselves experiencing intermittent operation, an audible decel sound could very well be indicative of at least the deceleration enleanment kicking in because the ECM thought you'd decelerated by closing the throttle at least some.

Valid point, hard for me to trouble shoot that.  I can watch the injectors and they match the RPM flux…question is which came first the input or a possible injector misfire.  Both, injectors are doing the same thing so I feel it is unlikely them.

Quote
With the VCI of the tuner, I recorded ... [and] noticed with NO physical change of the throttle, the “throttle position indication” dropped 100 RPM and the engine would follow.  To me this meant the bike was receiving a false input?

The TPS does not indicate in a value of "RPM".  I'm assuming you mean the TPS indication drops in both percentage value and in volts, whichever scale you're using.

I'd say there is a common factor so far in every one of these declarations/descriptions you've given, and they all lead me to believe that the ECM is incorrectly thinking you've decreased throttle position at times when your cable-driven butterfly has in fact not budged.  Am I correctly understanding that specific point?

If so, then I'd say you now know exactly where to look.  If it's an electrical problem you will not succeed in trying to cover it up by altering any portion of your tune.  You really need to eliminate all possible or actual electrical anomalies before proceeding with altering the calibration.  Since you aren't "much of a spark chaser" the simplest thing for you to do would be to carefully break then re-make all connections between the TPS and ECM.  If the problem persists, somehow obtain a known-good TPS and replace the one on your bike with it to see if you can replicate the problem.  If the problem continues, then it's got to be either in the ECM or the wiring between the TPS and ECM.

While I or any of several thousand other people could troubleshoot this for you in a beer or two's time, I'm reluctant to try to hold your hand on a walk-through of the process over the Internet.  Do you have an analog voltmeter at your disposal and do you feel comfortable that you can use it without physically damaging connector components while probing them?  If not, then there's absolutely no shame in getting the bike and someone who can competently diagnose electrical issues in the same room.

How about attaching your recorded datalog file here so I/we can have a look-see?

All excellent points.  I do not know where the TPS is, can you point me in the right direction.

I am comfortable using the volt meter, just not sure the process.

The data log, I tried to copy it without success.  Will give it another try later.

Thanks for all the assistance.

[glens]

Attached is a snippet from the '07 Softail wiring diagrams.  I've highlighted the lines, but not with the correct colors.  The colors and their positions in the connectors are shown in the diagram.

The TPS is on the end of the throttle butterfly shaft.  It'll be on the rear of it whereas your throttle cables hook to the wheel on the other end, the front.

You could hook up both the VCI and a computer to the bike and monitor the TPS output in real time, slowly and deliberately running the throttle open and closed with the ignition on but the engine not running.  Spend a little extra time going up and down through the area where the throttle is being held under the problem conditions you're reported.  You should not see any spiking, dipping, or skipping.  It should always be smooth transitions.  But this may not indicate all is well with the TPS circuit because the data is not coming from the ECM at a continuous and complete rate.  In fact you should select in the software the least number of data channels which includes TPS, and at the fastest rate you have available to you.

If you cannot in any way find evidence of a problem this does not necessarily mean there isn't one.  You only get so many frames of data per second from the ECM and a glitch may have occurred between collection times.

Hopefully, if this area is what's causing your grief you'll be able to clearly see it this way.

If you get what you consider to be a clean bill of health, then it's time to make sure and hook up an analog multimeter (one with a needle) to the TPS and check it that way.  If we need to do that I'll try to walk you through the process.  Whatever you do, don't merely pull the connectors and shove your meter probes into the connector sockets since you can easily damage them.  It'd not necessarily be the end of the world, but it could make more work for yourself than you need, as you'd then need to disassemble the connector and reform the component you'd messed up.

Try attaching the raw datalog file you'd gathered earlier to a post.  If you have to "zip" it up first to get it to attach, then do that.  I'd dearly like to see what you've got.

[cburch2]

glens,

The schematic and details on how to trouble shoot are awesome.  Life got to busy after work and hope to look at this tomorrow.

Again, THANKS!   

Craig

[cburch2]

glens,

Finally figured out the .zip, attached is my original data file.

Craig

[glens]

Yeah, I'm not seeing anything obvious in that log file.  It was only a bit more than a minute long and the bike wasn't moving or even up to temperature yet.  Do you have one that you've gotten while riding and run into the "problem"?