First, I want to thank all who have contributed to this forum over the years with more collective NT knowledge that has been a huge aid me and I assume others. My turn to hopefully give back.
Long story short (I hope). I was returning home from completing the Iron Butt 50CC Quest (cost to coast in under 50 hours) in May which was awesome when about the time I hit Amarillo, TX I had a check engine light come on indicating Throttle Body Sensor error. I made an unplanned stop there and stayed the next few nights trying to uncover the problem with no success. The problem seemed to "go away" but by the time I hit Little Rock, AR the problem returned. Lucky for me I found an outstanding Honda dealership there and they took me right in but they could not find anything other than possibly they thought a slightly loose battery connection - it wasn't the problem, and I don't like to over torque the battery terminals, but that was all they could do and reset the code for me. Off I went heading home. Made it home and rode many smaller day trips when the error code surfaced again.
Ok, time to play backyard mechanic and see what the problem is. I read everything on this forum and followed multiple lines of investigation and replacement of parts. New spark plug wires and caps (my NT a 2010 model) which seemed reasonable for a bike with over 50,000 miles and Florida heat - they were the originals. Next although I had cleaned each and every electrical connector as I learned from a wonderful YouTube by a British fellow, but yet I wasn't sure this was a rock solid solution, so I purchased a new sub-harness replacing the old one - better safe than sorry. One test suggested that the Idle Air Control Valve/Sensor might have not been up to spec. No problem, pull out the credit card and replace that too. (That wasn't the problem, so I have a spare) A vacuum leak? That might be the problem, so hello Visa and buy some new hose and replace all the vacuum lines - cheaper by the dozen, right?
Put it all back together only to find the error code didn't appear right away but the bike would not come down to idle rpm's. Something is wrong. With the help of a much brighter and experienced motorcycle mechanic friend, who originally thought one of the vacuum hoses was the problem, we got some carburetor cleaner and with the bike running sprayed the connectors (the rubber boots) that connect the throttle body to the cylinder heads - BINGO!! The rpm's increased and now we knew the problem that was causing the Throttle Body Sensor code (8) - pinholes or tiny cracks in the connectors were letting air into the engine and fooling the computer. I cannot see the holes or cracks, but I am guessing with heat they open up and cause the air flow into the engine messing up the air/fuel mixture so the computer isn't happy. Another shopping spree for more parts and we're now finally back in business - 2 months of no riding, but I am now confident that we found the root of the problem.
So. . . before you purchase a new throttle body (only $999.29 tonight only on Partzilla) you might want to check the connectors ($30.79 each) instead. Hope this helps others and I would appreciate it if our webmaster could please add this "tip" to the repair section of the forum as well, as others might appreciate the information.
Jim
PS - Thanks to Chris, I also don't need yoga now to get to the one bolt holding the connector to the throttle body!
Long story short (I hope). I was returning home from completing the Iron Butt 50CC Quest (cost to coast in under 50 hours) in May which was awesome when about the time I hit Amarillo, TX I had a check engine light come on indicating Throttle Body Sensor error. I made an unplanned stop there and stayed the next few nights trying to uncover the problem with no success. The problem seemed to "go away" but by the time I hit Little Rock, AR the problem returned. Lucky for me I found an outstanding Honda dealership there and they took me right in but they could not find anything other than possibly they thought a slightly loose battery connection - it wasn't the problem, and I don't like to over torque the battery terminals, but that was all they could do and reset the code for me. Off I went heading home. Made it home and rode many smaller day trips when the error code surfaced again.
Ok, time to play backyard mechanic and see what the problem is. I read everything on this forum and followed multiple lines of investigation and replacement of parts. New spark plug wires and caps (my NT a 2010 model) which seemed reasonable for a bike with over 50,000 miles and Florida heat - they were the originals. Next although I had cleaned each and every electrical connector as I learned from a wonderful YouTube by a British fellow, but yet I wasn't sure this was a rock solid solution, so I purchased a new sub-harness replacing the old one - better safe than sorry. One test suggested that the Idle Air Control Valve/Sensor might have not been up to spec. No problem, pull out the credit card and replace that too. (That wasn't the problem, so I have a spare) A vacuum leak? That might be the problem, so hello Visa and buy some new hose and replace all the vacuum lines - cheaper by the dozen, right?
Put it all back together only to find the error code didn't appear right away but the bike would not come down to idle rpm's. Something is wrong. With the help of a much brighter and experienced motorcycle mechanic friend, who originally thought one of the vacuum hoses was the problem, we got some carburetor cleaner and with the bike running sprayed the connectors (the rubber boots) that connect the throttle body to the cylinder heads - BINGO!! The rpm's increased and now we knew the problem that was causing the Throttle Body Sensor code (8) - pinholes or tiny cracks in the connectors were letting air into the engine and fooling the computer. I cannot see the holes or cracks, but I am guessing with heat they open up and cause the air flow into the engine messing up the air/fuel mixture so the computer isn't happy. Another shopping spree for more parts and we're now finally back in business - 2 months of no riding, but I am now confident that we found the root of the problem.
So. . . before you purchase a new throttle body (only $999.29 tonight only on Partzilla) you might want to check the connectors ($30.79 each) instead. Hope this helps others and I would appreciate it if our webmaster could please add this "tip" to the repair section of the forum as well, as others might appreciate the information.
Jim
PS - Thanks to Chris, I also don't need yoga now to get to the one bolt holding the connector to the throttle body!
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