Cold Stumble

[flat6bagger]

I have the stumble.
I just let it warm up or give it a bit more gas/feather the clutch for a split second when I take off cold.
Until someone mentions it,I do not notice it.
As far as it being a filter or screen issue,I don't think it has anything to do with that.
Here is why.
There appears to be more Goldwings/F6Bs with the stumble than don't have it.
Every one of them has different miles on them.
I don't believe all of these bikes can have a filter/screen issue.
On a side note...the stumble as it is called has never caused a concern for me.
I just ride.

[shooter]

I'm not saying that's it Steve. Just supposition. A cold engine can require twice as much fuel as a warm engine. That's why it goes away when it warms up. It could be in the programming in the ECU. Lots of could be all over the place. There is only one constant. It's short on fuel when cold.

[flat6bagger]

"It's short on fuel when cold"

That is a fact.

[53driver]

I am in FULL agreement that there is a fuel flow issue.
But is it one or all of the following:
Electrical
- The demand signal
- The demand signal feedback loop
- A sensor somewhere giving false information
Mechanical
- The fuel pump not responding to the demand flow (main jet / pilot jet issue??? lol )
- A filter
- Mechanical feedback in the throttle body

I believe it's in the ECU - no one with a Guhl reflash has had this problem.
Can't wait to get mine to him and back.

I also want to see if GaTeach's mech had the solution.

[shooter]

Steve I do know a couple guys on another forum that still had a problem. Sent the ECU back to Guhl a second time and no issues after that. If it was me I would tell Don about the problem so he could pay special attention to that area.

[Pumper]

Steve,
I believe also it is in the ECU...Fuel injection has a cold start circuit. That is controlled through the ECM of whatever vehicle it is.
Cold start stumbles, typically are a result of misinformation being sent (sensor) to the ECM. Hence the ECM will produce a lean condition.

Sensors are hard to diag. as they have gremlins and we all know how hard they are to catch...

Has anyone had a code thrown due to the stumble??

[shooter]

On a side note , you get that flash you better hang on in first and second. It ain't the same bike.

[53driver]

Steve,
I believe also it is in the ECU...Fuel injection has a cold start circuit. That is controlled through the ECM of whatever vehicle it is.
Cold start stumbles, typically are a result of misinformation being sent (sensor) to the ECM. Hence the ECM will produce a lean condition.

Sensors are hard to diag. as they have gremlins and we all know how hard they are to catch...

Has anyone had a code thrown due to the stumble??

Interesting point! I'll check the manual and see if there is a code for that that perhaps the MIL doesn't light up for as the bike does continue to run.
Thanks mate.

[53driver]

Steve I do know a couple guys on another forum that still had a problem. Sent the ECU back to Guhl a second time and no issues after that. If it was me I would tell Don about the problem so he could pay special attention to that area.

I shall - thank you.

On a side note , you get that flash you better hang on in first and second. It ain't the same bike.

I don't think I'll have a problem with that part!!!

[flat6bagger]

There is a guy on a GL forum that had to have his reflashed 3 times I believe he said before it took care of it.