What now? (bad idle and poor running)

I suggest you have an exorcism performed on your bike to rid it of any demons.
If it still runs poorly it can only be one thing....



Aliens!

I know, I'm so helpful.
Just the other day the left mirror started blowing around in the wind no matter how much I tightened. This morning I put an "O" ring in the equation and a flat washer and that problem is now gone.

About a week ago my fuel level quit working. It goes down but doesn't show when you put gas in. Raising the tank kinda fixes it and it starts the countdown again until the next fill up- another item on the "to be fixed" list.

Yeah, poltergeists all of a sudden.
alien.jpg
 
Ok, so I tried a few things this morning before work. I connected a hose to the MAP sensor and sucked on it- it held, so no obvious cracks or leaks. Still, when the other one comes in I'm going to replace that one.

Next I reset the ISCV. The TPS was at .64 not .60 like I set is just a week ago- hmmmm. It was 27℉, so maybe (?) that had something to do with it. Anyway, I adjusted it to 60. As I thought, there is no way to adjust the stepper motor for the second setting without the linkage. I turned the nut on the stepper and it had no effect- unless is was so far out and just needed to be turned a lot further. I suspect it needs to press against the idle screw cam to get a reading.

I reset adaptation.

It behaved perfectly to and from work, but experience tells me that I should expect it to act up again soon.

Plans for the next few days: replace vacuum hose, MAP sensor, check voltage on TPS, check voltage on coils. Am I forgetting anything?
 
probably has nothing to do with your problem
woke up around 3 this morning (dont know if it is my slow working brain or my mechanical brain) but something clicked.
in order to set tps to .60/.62 without stepper motor u would have to back off the idle stop screw to close throttle then set tps to .60/.62
 
probably has nothing to do with your problem
woke up around 3 this morning (dont know if it is my slow working brain or my mechanical brain) but something clicked.
in order to set tps to .60/.62 without stepper motor u would have to back off the idle stop screw to close throttle then set tps to .60/.62
I do my finest thinking waking up and unable to sleep- same problem ;-). Hmmm- that makes sense. @Kevin frazier ? Wondering if I should move it back to .64. Actually, it ran just fine though (for now, anyway).
 
No one is suggesting a bad coil, but I wonder since, when bad, they can act up intermittently, which is what my issue is doing. The bike ran great for days of hard riding and then suddenly this back-handed slap. If anyone agrees that could be it, do I just swap a new coil in each position one at a time and see if it clears up, or is there a more efficient way to test?
That's the way I would do it. Hate intermittent coil failures. It's too bad they don't always fail to an open position all the time. An ohmmeter may show that the coil is ok but when it gets hot.... no go... which is hard to catch with the meter. Swapping coils to see if the symptom disappears may be the only way to find it.

Haven't really heard of anyone who has had a coil failure to date but you could be the first.

Also, the TPS voltage setting of .60 volts is for a closed throttle reference setting for the ECM. I think the .72 is the run setting that the stepper tries to maintain when idling. If the stepper is removed, make sure your throttle plates are closed then set TPS to .60. Once that is done I'd turn the idle screw up to the rpms you want for idle.
 
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That's the way I would do it. Hate intermittent coil failures. It's too bad they don't always fail to an open position all the time. An ohmmeter may show that the coil is ok but when it gets hot.... no go... which is hard to catch with the meter. Swapping coils to see if the symptom disappears may be the only way to find it.

Haven't really heard of anyone who has had a coil failure to date but you could be the first.
Interesting- but I think the coils are the same ones used on the Bonneville. When I got back into riding and reading Bonneville forums there was a lot of talk of coil failures. I'll do the ohm test and if all good will start swapping after I try a few other things on the list. Thanks
 
the bunny has two ears per unit lol
i have found that when checking for resistance the most failures occur when unit reaches or exceeds operating temperature.
i often let vehicles run while eating lunch then when i check one that is suppose to be 27 ohms it goes to 300,000 ohms failure.
checking cold is probably useless.
rather than read 8 pages let me ask this question does it act up more when when cold or hot.
 
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