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Rough Idle & Ignition Firing When Warm - Sparkplug Cap Replacement Not So Good Idea

bmacneil2008

Tuned and Synch'ed
Joined
Aug 16, 2014
Messages
53
Location
Charleston, SC
With Todd's 100% help, I installed the full monty of PC5/AT and ECU reflash 2 years ago. Bike ran/runs perfect, much better than stock (2009). However, I am having some idling issues after the bike has been run for a few miles and even on the throttle is not running 'clean'. I have decided to go back to a stock setup and remove the PC5/AT. I assume I need to have the dealer reflash the ECU to stock after I reinstall the stock CO2 sensor and is back to stock.

The bike ran great with all the mods, is not the issue, I just need to track down what is going on now. It all started when I replaced the spark plug caps. Not sure why I did so but in the forums riders stated the stock caps could become an issue. I had the bike in for a warrantied alternator replacement, the pulley shaft snapped, and had them replace the caps. Well, the mechanic pulled so hard on one HT coil leads he severed the wires inside, left side. Was getting the red engine light after. I replaced the HT wire ($3 from NAPA) instead of taking the bike back to the dealer as is a 6 hour round trip, towing, and the bike ran 100% better but still the issue when warmed up after a 10 mile idle or so is not . I believe is the right side that is the issue and now am replacing both sides with OEM wires ($120) just to get back to ground zero, and w/o all the goodies. Not fun in the sun removing the cowling assemly to get to the coils.

I have the diag cables, can I reflash the ECU back to stock w/o going to the dealer?

Thanks.

Camping ride up to Unicoi, TN -

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Robert M.
 
If it ran great for 2 years why would you take all that off to find the problem. Apparently your mechanic is not so good and might of screwed something up. I would find a new mechanic and start with what he messed with.
 
The bike should run fine with Todds map and no PCV or AT. It may not be an ideal tune but it should not give u any running issuses unless the map is corrupt but it is unlikely as long as they did not do anything to it. it also will not be the O2 sensors as Todds map disables them.

Sounds like the leads are the issue. Double check the wires and caps again to make sure there are no breaks. Known issue with these is how the coil end comes loose. Pull the plug off the coil and make sure it is a tight connection. I zip tie mine in place another would not come loose.

R u sure they didn't try to reflash your ecu when it was there. Some dealers will look for updates and reflash. If they did that then it would run like crap without the O2 probes installed as the stock map needs them to run. The PCV and AT would do nothing as the bike is running in closed loop. All the symptoms fit. When u first start the bike it will not need the O2 sensors. Once it starts to warm up the sensors come on line for closed loop running.

Sound like u need to talk to your dealer.
 
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Make sure your coil wires are fully plugged into the coils too.
 
Like Kiwi & Canuck1969 said.
My 2cents is: It sounds like you are rebuilding the wheel. I live by the "KISS" rule: Keep It Simple Sweetheart
Contact dealer per above first. If no Joy replace both leads.
 
The bike should run fine with Todds map and no PCV or AT. It may not be an ideal tune but it should not give u any running issuses unless the map is corrupt but it is unlikely as long as they did not do anything to it. it also will not be the O2 sensors as Todds map disables them.

Sounds like the leads are the issue. Double check the wires and caps again to make sure there are no breaks. Known issue with these is how the coil end comes loose. Pull the plug off the coil and make sure it is a tight connection. I zip tie mine in place another would not come loose.

R u sure they didn't try to reflash your ecu when it was there. Some dealers will look for updates and reflash. If they did that then it would run like crap without the O2 probes installed as the stock map needs them to run. The PCV and AT would do nothing as the bike is running in closed loop. All the symptoms fit. When u first start the bike it will not need the O2 sensors. Once it starts to warm up the sensors come on line for closed loop running.

Sound like u need to talk to your dealer.

Agreed with all comments. Ordered and received new OEM leads and caps. Will install this weekend and then see if the issue is resolved. The service manager told me when I picked up the bike that when the mechanic was trying to pull the stock caps off, took alot of muscle. So when I got home (3 hours 1 way is why trying to repair myself) and took the bike for a test ride it was missing and then the red light came on. I knew was due to the NGK caps install. I inspected them and the caps were loose, not screwed into the coil wire securely. I did this and the bike ran better but still not smoothly and the light was still on. I then wiggled the left coil wire and the light went out, so determined when the mechanic pulled the OEM caps off he somehow damaged the coil wire inside the lead. I installed a new coil wire and the bike ran 90% better, light out, but think there may be a similar issue with the right side but not as severe. Only occurs after heated up, that is somewhat a mystery as why not when cold to. The dealership, until this, has been fantastic, so I mark it up to a 'just a bad day at the office' happens to all of us.

Curious, you mention I can run with Todd's map only. So, no O2 sensor at all. Currently it runs into the AT module. I would like to remove both the PC5 and AT as think is just one more thing that can short, go out, etc. Is this possible?

Never thought to ask the dealer if they reset the ECU, worth knowing, good suggestion.

Thanks again....
 
If it ran great for 2 years why would you take all that off to find the problem. Apparently your mechanic is not so good and might of screwed something up. I would find a new mechanic and start with what he messed with.

Next Guzzi dealer is 6 hours 1 way, so need to have faith in my local, 3 hours 1 way, dealer. But you are right, very frustrating. My bad in not taking it for a ride when there......coulda, woulda, shoulda.
 
In order to run a PCV and AT the lambda (O2) probes need to be turned off in the ecu. This allows the PCV and AT to take over using their own probes otherwise the ecu will keep looking for the stock probes. This is why u remove the stock ones and install the AT probes. You can just run Todds base map without any probes if AT is removed or disconnected. The ecu won't look for them. . If the dealer reset your ecu then you have to run the stock probes.

Check the plug to the actual coil to make sure it is tight. They can come loose and cause similar issues.
 
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