No fire/rear cylinder
No fire/rear cylinder
Last weekend on my way home (about 15 miles from home) I lost fire to rear cylinder on my 2007 SG. I putted her on home on one cylinder. Today I went and got new wires and ignition coil. I thought it was the coil but did wires while at it. Well all back together(removed tank) and still no fire. What else could it be. The only thing left is ECM but not sure how to check with meter. Is it 12 volts out at each connection for the cylinders? I know one of you can help.
I originally Checked for spark and thought I had a bad wire. Swapped wires and still no spark. Ohmed wire and was not reading well so no loss replacing them. I figured it was the coil because of no fire with good wire so decided to just replace all of it. Now I am not sure where to check. The diagrams show the ECM as the only other link. Not sure how to check output on this. I had other issues with the ECM in the past but was able to "jump" around it. It was a ground wire issue going into the computer. I may just haveto replace it.
Seasoned HDF Member
Joined: Jun 2006
Posts: 30,881
Likes: 32,991
From: King George, VA
I had a similar problem with my 06RG. Lost fire in the rear cylinder. Turned out to be a broken injector wire lead. The vibration of the engine broke the wire inside the insulation so it wasn't visible. With the broken ends of the wire being very close to each other, an ohm check showed the wire was good, but later on after finding it we determined that it would show as intermitent if the wire was flexed while the VOM was attached. The break will probably be in the harness wire were it comes off the backbone of the bike and leads down to the injector.
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I am not getting an injecter code. I would never have guessed a broken wire to an injecter would cause a no fire situation. But this may be something to check.
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Road Warrior
Joined: May 2009
Posts: 1,537
Likes: 4
From: The Great River Road, Wisconsin
The code just reads no combustion, which could be caused by no fuel or no spark (or a hole in something, bad valves causing no compression, but you are not there yet).
Sounds like you have access to a multi meter, so you could find a junction to the injectors and check continuity (resistance). Not sure how many ohms they are, but they should be within 10% of each other.
Sounds like you have access to a multi meter, so you could find a junction to the injectors and check continuity (resistance). Not sure how many ohms they are, but they should be within 10% of each other.