Engine Miss /Skip Help Please!

[rwg375]

I have a 2009. Having miss or skip while cruising. Had intermittent shut off problems. Installed after market ground spider, synched throttle bodies, changed plugs, installed LED driving lights. It has picked up miss or skip which make riding not enjoyable at all. Sent to dealer for a full wiring recall. Skip still there. Checked throttle body sync, all good. Pulled plugs, all appear good except #4 being darker. Installed new plugs. Did throttle position sensor test using diagnostic screen, all appeared good. Am at a loss now, anyone got any ideas. Please help.......

 

[ionbeam]

Does it skip in any gear, at any rpm or is it more specific to speed/gear/rpm/hot/cold?

There is the always popular reply to these symptoms --> Check to see that your battery terminals are tight.

 

[rwg375]

Thanks for your quick reply. Skip is any gear. more noticeable at lower RPMs, but is still there at higher rpms. Seems to do it hot or cold. Can even notice it on center stand just running engine. Will check battery connections and report back. Thanks again for the help.

 

[ahchiu]

Check your ground spyder connection and + and - terminals on your battery and make sure they are tight, sounds like a electrical problem and the ECU is not getting good power source, the vibration may be causing a weak connection.

 

[wa2fst]

Just a thought...spark plug caps? Unscrew from the coil wires and check the resistance.

 

[rwg375]

Just checked. Skip is happening cold or warmed up. Removed power wire to installed led lights. cleaned and tightend battery connections. Skip still there. Gonna check ecu connector and plug caps. Seems I balanced throttle bodies to what # 3 was at. Is there a flow all should be set at. Seems I remember I had to turn down 1-2-4 to match # 3. Please remember on plug check, something going on with #4 either misfire or running rich. Thanks for the help.

 

[ionbeam]

Roll your mouse pointer over any word(s) with a dotted underline and a text box with additional info will pop open.

More questions Did the miss/skip suddenly start or has it been gradually getting worse? Did you do any maintenance, fiddle with or in any other way disturb nuts 'n bolts from their normal resting positions on or slightly before the time the miskip started? On the one hand it reads like you are familiar with normal motorcycle maintenance, adjustments and have and read the FSM. On the other hand, this often leads to messin' with stuff that the ordinary neophyte would never get into.

While you were checking the TPS, did you find any codes stored in history?

KISS.

Edit: I see the OP and I had a cross post with his arriving to this thread just as I was clicking send.

 

[rwg375]

Only code in history was trip over. Not a current code. Does it still have to be cleared for normal operation? Seems to have started after installing after market ground harness, installing led driving lights, synching TBs, and changing plugs. Recall harness has been installed, plugs changed, TB synch checked, lights disconnected and battery connections checked. Misfire/ skip remains. Thanks

 

[Fred W]

Seems to have started after installing after market ground harness, installing led driving lights, synching TBs, and changing plugs.

The spark plug cap may be loose on the cable. There is a male screw thread in cap that augers into the center of the cable.

Make sure that all of these connections are tight (especially on the one that you mentioned earlier has a darker colored plug).

 

[kaitsdad]

Ground (neg) battery wire connects to the engine on the right side, behind and below the headers. This is another possible loose ground point.

 

[RaYzerman19]

Is the fuel more than two weeks old, ie, bike sitting for two weeks or more? Could be phase separation of ethanol fuel, fix with some Seafoam, or isopropanol to dissolve the water.

Also, define your 'skip' better, hard to diagnose and a more detailed description would be helpful.

 

[raven09]

I'm having a similar problem with my '09 and it's driving me nuts. Did all the checks above, tbs, plugs, Seafoam, plug caps, CO +10, etc. , problem still persists. Dealer says bike needs a Power Commander...

 

[Geezer]

Since you did the TBS, did you verify that all four rubber caps are on?

 

[joebiodiesel]

If it does it at idle, the first order of business would be to identify which cylinder is missing. You can do this a few different ways.

1) If you have one of those non contact temperature guns, shoot each exhaust header pipe individually to find the cool one. That's the cylinder with the miss.

2) Don't have one of those? Lift the tank and pull one spark plug wire off at a time until you find the dead cylinder. Even though the coils on our bikes fire 2 cylinders at a time(needing both plugs to be connected to make a complete circuit), it should still work just fine. The disconnected wire has enough capacitance to fire the paired cylinder.

So, in short, just pull a plug wire off each cylinder, one at a time, until you identify which cylinder has the miss. After that we can determine whether it if a spark, fuel or compression problem.

Once you identify the cylinder, put an old spark plug in that wire and run the bike to see if you have good spark available. If you do, report back and we can go further.

Joe

Joe

 

[ionbeam]

...Once you identify the cylinder, put an old spark plug in that wire and run the bike to see if you have good spark available...

Or use the diAG actuator function to fire the plug so that you don't have to run the bike.

 

[rwg375]

Miss or Skip is, with engine running is sounds and feels like a plugs decides not to fire. This is randon and has no stead beat. Not to noticable at idle but it is there. seem to be worse in the 2000 to 4000 range. Can feel it missing when riding. Idles good and excellerates well, but notice this miss at steady throttle. Checked all boot to wire connections good. Held thottle at 3000 for a couple minutes with it missing, shut it down, and shot ex pipes with IR gun. All temps same + or- 10 degrees. Pulled plugs, all look good and the same. Can not identify which cylinder it is. May be random on all. Gas is kinda old, topped off with 1.5 galons of fresh and sea foam. Rode about 15 miles no help. Gonna check spark on all plugs now. Thanks for your help.

 

[03HiYoSilver]

A bad Spark Plug will do this too...even though they look good.

Good Luck with your fix...

 

[mcatrophy]

1320093731[/url]' post='910491']... pull one spark plug wire off at a time until you find the dead cylinder. Even though the coils on our bikes fire 2 cylinders at a time(needing both plugs to be connected to make a complete circuit), it should still work just fine. The disconnected wire has enough capacitance to fire the paired cylinder.

...

Joe

If you do that you run the risk of breaking down the insulation in the coil or of the plug lead. Either short the disconnected lead to the engine or put it on a spare spark plug with its outer connected to the engine.

 

[rwg375]

Checked spark plugs with diaganostics, all looked like firing good. All boots to wires tight. reintalled, still the skip. maybe i need to grease the muffler bearings. LOL.