2018 Ultra Classic – Will not start
Seasoned HDF Member
Joined: Jan 2007
Posts: 5,626
Likes: 4,080
From: Virginia
Well it’s either a fuel delivery issue or a spark issue. Since you say the battery tested good and I doubt gas would go bad in less than 2 months, I’m leaning towards something in your fuel delivery system. The LO RNG could be caused by a bad sending unit in your tank but that shouldn’t keep your bike from starting. Take care of the simple stuff before you start looking for a problem inside the tank, all electrical connections tight? I see you swapped bars in November, maybe a crimped wire at the switch pack? Frame ground tight? Good luck.
Thread Starter
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4th Gear
Joined: Oct 2019
Posts: 8
Likes: 2
From: Elsmere ky
Did you store the bike with ethanol gas? Did you add a fuel stabilizer? When ethanol gas first came out I had to have several small engine carbs rebuilt. Including my Kawasaki Vulcan 750.
I always store my bike with nonethanol gas, and add a fuel stabilizer. Otherwise the gas gets gummy.
You could try adding some Seafoam.
I always store my bike with nonethanol gas, and add a fuel stabilizer. Otherwise the gas gets gummy.
You could try adding some Seafoam.
Thread Starter
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4th Gear
Joined: Oct 2019
Posts: 8
Likes: 2
From: Elsmere ky
Well it’s either a fuel delivery issue or a spark issue. Since you say the battery tested good and I doubt gas would go bad in less than 2 months, I’m leaning towards something in your fuel delivery system. The LO RNG could be caused by a bad sending unit in your tank but that shouldn’t keep your bike from starting. Take care of the simple stuff before you start looking for a problem inside the tank, all electrical connections tight? I see you swapped bars in November, maybe a crimped wire at the switch pack? Frame ground tight? Good luck.
Yea, the bars were swapped back in 2019. The bike started and was pulled out of the garage, but did not start 2 hours later when I wanted to pull it back in. Good into, thanks.
Supporter
Joined: Jan 2007
Posts: 15,788
Likes: 5,625
From: along the shore of Mishigami
This is a shot in the dark. Try doing an ECM reset, ignition. on 5 secs., ignition off 5 secs.. Do this 5 cycles. I would also for ***** and grins, first swap system relay and start relay, if nothing works then try the ECM reset.
Outstanding HDF Member
Joined: Feb 2015
Posts: 2,414
Likes: 433
From: Arkansas
OK, were all guessing at this point. Does the cylinders get fuel, spark and air? If not what part is missing. I asked this question on my first post on this topic but it was never answered. If we can get an idea what is missing we can hazard an educated guess as to what the root cause is.
Outstanding HDF Member
Joined: Feb 2015
Posts: 2,414
Likes: 433
From: Arkansas
With the lo rng check the fuel pump plug and ensure that it is fully seated, does fuel pump prime?
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Thread Starter
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4th Gear
Joined: Oct 2019
Posts: 8
Likes: 2
From: Elsmere ky
OK, were all guessing at this point. Does the cylinders get fuel, spark and air? If not what part is missing. I asked this question on my first post on this topic but it was never answered. If we can get an idea what is missing we can hazard an educated guess as to what the root cause is.
Thread Starter
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4th Gear
Joined: Oct 2019
Posts: 8
Likes: 2
From: Elsmere ky
Thanks for the help.
