Calling all FatBoy Lo Owners
Seasoned HDF Member
Joined: Aug 2015
Posts: 10,374
Likes: 518
From: Southern Arizona
Sounds like you have a vacuum leak Dan. Sucking air some place it shouldn't. Look around the throttle body there are some ports that are capped and those caps can deteriorate over the years. Check the boots where it meets the heads, with the bike running, spray a little shot of starter fluid at them and see if idle changes. Don't want to run it that way too long, it will get lean, hot and can cause some serious damage
Stellar HDF Member
Joined: Mar 2012
Posts: 2,019
Likes: 599
From: Columbus, OH
Voltage regulator seemed like a long shot, but this is where internet diagnostics fall short. I would want to see it hooked up to something that can read data from the ECM and see what IAC valve is doing. If I had to guess from the description of the code. I would say the IAC valve is closing trying to slow the idle and has reached it's limit but engine RPM is too high for for the IAC position. That's just a wild *** guess sitting here at work, I wanted to look the code up but haven't been home before 9pm any night this week and the 4:30am alarm keeps my evening activities to a minimum. I'll see what I can find out this weekend Dan
Seasoned HDF Member
Joined: Aug 2015
Posts: 10,374
Likes: 518
From: Southern Arizona
The code is P0507, ECM, it says, ( Idle Air Control System RPM Higher than Expected)
Second code sais Speedo, B1210 had something to do with the speedo sensor reading the level of gas wrong.
I appreciate the help Chuck. I'll also tell the mechanic of your first guess. I don't take it in till wednesday
Second code sais Speedo, B1210 had something to do with the speedo sensor reading the level of gas wrong.
I appreciate the help Chuck. I'll also tell the mechanic of your first guess. I don't take it in till wednesday
Seasoned HDF Member
Joined: Aug 2015
Posts: 10,374
Likes: 518
From: Southern Arizona
Voltage regulator seemed like a long shot, but this is where internet diagnostics fall short. I would want to see it hooked up to something that can read data from the ECM and see what IAC valve is doing. If I had to guess from the description of the code. I would say the IAC valve is closing trying to slow the idle and has reached it's limit but engine RPM is too high for for the IAC position. That's just a wild *** guess sitting here at work, I wanted to look the code up but haven't been home before 9pm any night this week and the 4:30am alarm keeps my evening activities to a minimum. I'll see what I can find out this weekend Dan
Stellar HDF Member
Joined: Mar 2012
Posts: 2,019
Likes: 599
From: Columbus, OH
Good to hear they got your bike figured out
Seasoned HDF Member
Joined: Aug 2015
Posts: 10,374
Likes: 518
From: Southern Arizona
You figured it out, i told them what you said so it was the first thing they looked at. Thanks my friend.
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Road Master
Joined: Apr 2016
Posts: 816
Likes: 203
From: Alaska
Speaking of new tires. I need to let the air out of my front so I don't ride until I replace it...lol
Seasoned HDF Member
Joined: Aug 2015
Posts: 10,374
Likes: 518
From: Southern Arizona
my front will last twice as long as the back