2008 GSX-R600 with fault code C27 (IGNITION SIGNAL #4)

[motodave]

Hello everyone. My bike is running rough as if it's on one or two cylinders with the FI light solid. I put my bike in dealer mode and uncovered code C27 which is an issue with ignition signal #4.

My bike has just over 20000kms on it and is well taken care of. Any ideas on how to go about fixing this on my own or is it time to take my baby to a shop?

Any advice would be greatly appreciated.

--Dave

 

[Red_Liner740]

how hands on are you? how comfortable are you in removing the fairings/tank and getting into the engine?

sounds to me like one of the ignition coils is gone caput...

best way to trouble shoot that:

fire up the engine and use a water bottle to spray the exhaust headers...one of the pipes will not evaporate off right away. This is your cylinder with no ignition.

get to the top of the valve cover like you would to change the spark plugs and remove the coils....swap the coil from the dead cylinder to another cylinder and connect everything back up and fire it up again. See if the problem followed the coil or if it remained on the same cylinder.

While you're at it, change the spark plugs...

This will let you remove one of the unknown in the system. after that it gets trickier.

now lets just wait for freakeyguy to whore him self out with some stupid left field advice and a mandatory "i can look at it for ya, PM ME!"

 

[Brian P]

Ohhh boyyyyy ...

The last one of those that I saw with that code, the problem turned out to be loose pins at the ECU main harness connector combined with a failed secondary throttle valve actuator, and it was real sonofagun to troubleshoot and an even worse sonofagun to fix.

Follow the procedure in the above post. The process of doing this might uncover a loose connection somewhere, in which case, you are all set. Otherwise, if the fault code moves to the other cylinder that you swapped coils with, the problem is likely to be a bad coil. If the fault code stays with cylinder 4 (or, if as in the other case that I saw, you get a whole bunch of random codes that are different every time), you will have to do further digging.

 

[motodave]

Thanks very much for the very helpful information! I have confirmed cylinder #4 is not firing. I have one more question - If my repair efforts fail will I harm the engine if I drive it to the shop while it's only running on 3 cylinders?

Thanks again!

Dave

 

[invictus43]

Thanks very much for the very helpful information! I have confirmed cylinder #4 is not firing. I have one more question - If my repair efforts fail will I harm the engine if I drive it to the shop while it's only running on 3 cylinders?

Thanks again!

Dave

Well, it's never great to operate an engine with unburned fuel going through it.. Having said that, if it's not too far and you go easy, you will probably be fine. I've ridden bikes with fouled plugs for miles and they survived ok..although I usually got rid of the bike 10,000kms later..

 

[Red_Liner740]

Short distance? No problem. Longer distance or longer than an hour and tue unburnt fuel will wash away oil lubricating the cylinder and thin down the oil. This won't happen right away but it will harm the engine with prolonged running.

 

[motodave]

Thanks again for the info everyone - this is very helpful!

When I got home from work I took the airbox off and found the problem. Mice chewed through some wires in the loom feeding the coils...they must have been at it for awhile.


fig.1 - overview of loom showing compromised area.


fig.2 - Zoomed in view of compromised area. The orange wires leading in the cap are chewed, one all the way through.


1. Does anyone know what this part of the wire loom does (upper arrow)?

FYI: The part of the harness shown in fig. 2 is called the ground bus.