Harley Davidson Forums banner

1 - 9 of 9 Posts

·
Registered
Joined
·
3 Posts
Discussion Starter #1
Went out to start my bike started right away idol for a while then revved up without me touching the throttle then went down to idol again.turned off bike try to start it up once again started right back up.The next day I got on my bike turned it on hit starter and would not start,Killed battery trying to start it.Can anyone help with this one.changed out all fuses still would not start.
 

·
Registered
Joined
·
543 Posts
How are your plugs, are you getting spark?

Also I strongly recommend that you grab a service manual for your bike.
 

·
Registered
Joined
·
3 Posts
Discussion Starter #4
Yes I did check the plugs ,also took the plug out hit the starter and rubbed it against the frame no spark.thanks lone rider anything else to check.
 

·
Registered
Joined
·
7,340 Posts
I don't know much about the efi on bikes but is there anyway you can verify its getting fuel? Sounds like the first start that it may have been going into choke mode maybe starving of fuel. Just a guess.
On a traditional carb you are "choking" off the air, not the fuel. A carbed Harley's "choke" isn't really a choke at all, it actually adds extra fuel. EFI does the same thing automatically based on sensor data.

A lot of times the idle will become erratic if the engine temperature sensor fails. That sensor screws into the back of the front cylinder. You'll see it if you pop off the horn.

There's also a sensor for the air intake temperature. It mounts in the throttle body. There's a MAP (manifold air pressure) sensor that plugs in the intake manifold behind the throttle body. And, there's a TPS (throttle position sensor) that sends the throttle position to the ECM.

Failure of any of those and the EFI not going to behave. I'd start there for sure.

There should be a way to test them all with a multi-meter. You'll find those tests in either the service manual or electrical diagnostics manual. You may even get lucky and find the test specs online. I wouldn't just start replacing parts. You'll go broke!
 

·
Keep on Ridin’
Joined
·
8,054 Posts
Chas, would any of the sensor failures trigger a DTC?

--
 

·
Registered
Joined
·
7,340 Posts
Chas, would any of the sensor failures trigger a DTC?

--
They should and likely there's a code specific to each. On that bike, you have to pull them using the jumper/flash method. Dave has a sticky for it in electrical.
 

·
Registered
Joined
·
147 Posts
On a traditional carb you are "choking" off the air, not the fuel. A carbed Harley's "choke" isn't really a choke at all, it actually adds extra fuel. EFI does the same thing automatically based on sensor data.

A lot of times the idle will become erratic if the engine temperature sensor fails. That sensor screws into the back of the front cylinder. You'll see it if you pop off the horn.

There's also a sensor for the air intake temperature. It mounts in the throttle body. There's a MAP (manifold air pressure) sensor that plugs in the intake manifold behind the throttle body. And, there's a TPS (throttle position sensor) that sends the throttle position to the ECM.

Failure of any of those and the EFI not going to behave. I'd start there for sure.

There should be a way to test them all with a multi-meter. You'll find those tests in either the service manual or electrical diagnostics manual. You may even get lucky and find the test specs online. I wouldn't just start replacing parts. You'll go broke!
I guess I was a little bass ackwards there. Lol. Thanks!
 
1 - 9 of 9 Posts
Top