MicroSquirt.com read only forum (Jan.15,2018)

Hoping someone can afford some assistance, I've attached a couple of data logs to help display hopefully, the problem.
I've had a lean swing when you come away from low throttle (or deceleration point) where by a relatively stable AFR will swing right over to 18, and stay there while the throttle is opened (and held from further increase to avoid a bad surge). I've attempted to go back to earlier saved files where I felt this wasn't happening, without success. Equally, tried "too numerous" to mention variations in the basics, it still remains. Accel enrichments have been turned off to no avail, equally, Extau, EGO, Automatic Mixture, etc. have all been disabled without effect on the lean swing.
Any/all help appreciated in advance. (hoping not to have to put bike away for season with an end like this, as well however will be hard to push much further with cold and snow on the doorstep).
If more detail required, will post it.
Lorne

One thing I noted seemed to be increased MiliSeconds of fuel numbers during that time when AFR climbed very lean which to me would suggest perhaps the MicroSquirt is attempting to address the lean situation. What else can affect the injectors like that then, I don't feel I have a mechanical issue. Fuel pressure remains rock solid through the lean phase. Can a setting on the injectors cause them to be sidetracked as the rest of the system attempts to behave normally? I won't feel bad if its a rather simplistic setting I've missed but would appreciate a comment.
This must have happened to others somehow, anyone?

Could you please post a copy of the MSQ along with the data logs? I generally prefer to look at both at once. I'll let you know what I find once I have both.

Hi Matt, attached file for reference. I have to believe I changed something during a fairly long trip back during late summer time, during which I started noting the lean tendancies surfacing.
Thanks in advance for help.
Lorne

Thank you. Looks like the ECU is commanding an amount of fuel delivery that should be all right at that point. What is the resistance on your injectors?

Those were the Delphi "High Impedance" injectors from your store (42lbs @ 43.5psi, I'm running about 49psi right now).
Lorne

Is the case getting hot when this happens?

Hi Matt, I haven't ever noted heat on the ecu case, however it is also mount somewhat out of the way and I've not really been checking it. Are you thinking the injectors are staying shut from the drivers being out of sorts? I believe those settings are right on with the recomendations with high impedance units.
( Lenthy tangent comments editted, see next post).
Thanks for your help,
Lorne.

Matt, your touching on something that I have to add to, perhaps very significant.
During the summer I started reducing the RT dash back to basic, and ended up running without a fuel pressure gauge for a fair while. During that time, a defective (on my part) fuel regulator drain fitting suffered with a restricted elbow back to tank side. This brought the fuel pressure up in varying degrees to around 80psi or so till I clued into itwhat was going on.

Being rated I note @ 49lbs maximum, what happens as pressure to an injector is raised as such, beyond that spec?

Or, would the M.S. drivers be suseptible to damage?

Is there a way to detect if excess heat is/has developed within the M.S. and would this then require some repair, or would injectors being replaced (assuming defect) allow a return on its part to "normal" ?

How does the injection test mode on the far right "tools" menu of MegaTune work, is that a useful tool on this line of thought?

Thanks for I suspect the direction to get back onto the actual requirement and success.
Sincerely,

Lorne

This definitely sounds like a hardware issue. Usually too much fuel pressure will make injectors stick closed but probably won't cause long term damage. It could be the drivers but could also be the injectors - or more fuel pressure gremlins.