Re: [ST] Stalling

[Jim Crate <jim@xxxxxxxxxxxxxx>]

Just thought I'd update everyone on the stalling problem.  I don't  
know if it is fixed yet, but I did do a couple things.

I dumped a full bottle of Redline SI-1 fuel injector cleaner in with  
a full tank of gas, and went on a trip down to Miami (140 miles of  
mostly high-speed super-slab, the first 70 miles I rarely drop below  
90).  Fuel mileage for that tank was slightly improved over normal to  
43 mpg.  Haven't finished off the next tank yet to see how it fared  
on the return trip, but I think it is getting close to 200 miles and  
the fuel light is not on yet, so it is not too bad.

I also took the bike apart last night to have a look at the plugs and  
clean the idle stepper plunger ("encouraged" by my friend with the  
Daytona 600 wanting to see what was under the airbox!).  I figured I  
might as well see, since when he had his airbox off the other day I  
convinced him to remove the secondary butterfly plates and now his  
bike is a good bit faster than mine!  So, we got to work and had the  
airbox off in short order.  Another friend stopped by, while they  
talked I removed and cleaned the idle stepper motor plunger and  
housing.  It did have a bit of gunk on it.  Other friend left, when  
putting it back together I discovered that because I had accidentally  
pulled the plunger out a little, now it wouldn't go back together and  
it didn't feel like we could just push the plunger back down.  So, I  
turned on the ignition to see if it would retract itself.  It moved a  
tiny bit, maybe that would work.  Turned off the ignition, and  
suddenly the stepper motor started buzzing again.  All of a sudden,  
the plunger SHOT off the stepper motor, followed closely by the  
spring that was pushing it!  Shit, never expected that to happen  
*after* turning off the ignition.  Both my friend and I have worked  
on a few bikes and several cars, and never saw anything like that!   
We found the pieces and looked at everything.  The plunger is driven  
up and down by a worm gear, and when the ignition is turned off the  
idle stepper motor resets itself by turning until it is completely  
disengaged, then retracting itself to a known point.  Very  
interesting...  Easy enough to put back together by holding the  
plunger down to the motor by hand, then cycling the ignition to let  
it retract itself.

Didn't take long after that to put everything back together.  Idle  
seemed steady this morning, but I discovered I have a check engine  
light, probably from turning on the ignition while the airbox temp  
sensor was unplugged.  I'll use my neighbor's ODB2 scanner to check  
and reset that today.

I did check the plugs too, the gap was still good, plugs looked  
perfect. Definitely nothing wrong there.  It was also cool to be able  
to see straight down the throttle bodies to the valves.

I haven't ridden enough to see if it is really fixed yet.  It didn't  
try to stall this morning, though.

Jim

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