Bike has been running fine. Went to Sturgis, not any problem at all. Today out of the blue it just turns over and would not start. Checked fuses, listened for fuel pump all is good. Shot a lil starter fluid in air cleaner and she started right up and ran fine. Plenty of gas in the tank. Any ideas? Would a fuel filter be the problem? Seems to start ok for now. Bike has a lil over 20k on it.....

 

A couple of easy items to check. Connector toto Crank position sensor, make sure it's tight. Disconnect the ECM, spray some contact cleaner in pins and sockets, reconnect. Check the connection at the fuel tank to injectors. A CPS reads the flywheel and tells the ECM to energize ignition coil to fire plugs at the same time the ECM will activate the injectors to deliver fuel to the cylinders.

 

Thanks for the response! I'll give those a look tomorrow.....

 

The fuel line quick disconnect on the fuel tank has caused this in the past. Unpredictably, it will cut off fuel, my best guess is from vibrating out of the fully seated position. Disconnecting it and reconnecting it usually fixes it.

 

I will check that as well. Thanks

 

Well not sure why it started before with a squirt of starting fluid, but it ain't startin now lol. I'm leaning towards a no spark problem I believe. Rechecked all fuses and looked for codes. No codes and fuses are good. Battery is fully charged and plugs and wires were changed last March. I've got a Power Commander V on it but have disconnected it and still won't start. Could a bad cps sensor cause a no start?

 

Think you are saying it won't stay running but a shot of starter fluid will get it running but it dies when it runs out of it
So my opinion is fuel.

It's not electrical.

Could be filter but it would have had to have had a bad load of fuel to stop it up. But no telling. A pressure check is a check for that. About 65 psi on injectors but hard to do without a hookup.


​​​​​​Start it with spray and hold throttle open a 1/4 turn above idle? Will it stay running? If so it either wet bad fuel or filter.

Did you fill up at any bad rough looking stops.

If it will run with throttle opening, I would pull off fuel with a kero syphon and refill a couple gallons of premium 10% ethanol gas. That will get the rest of the moisture.

 

Thanks for the quick reply. The other day it wouldn't start and I gave it a start of fluid and it did start, and continued to start all day. Now after sitting for 2 days I try and start it and no joy. Gave it a few shots of fluid and still won't start. Not even a cough. Just cranks. So that's why I'm thinking no spark. Cleaned all connectors to injectors and I do hear the pump kick on.....

 

If it's bad water logged fuel like 10% can get, when you first pump it, it will run. Usually the next day after water settles out, that's what is picked up.

Could be if it is that, spark is easy to check. Fuel pressure not so much. Remember, older Harley's need one plug in to get fire. But all you need to do is pull a wire. Get your wife to hold her finger over the end and tell her don't let anything out. Now crank it.

If she walks away cussing you out, you will know fire is good.

Or you can push a good plug on boot and ground threads to head and watch for fire. I have a plug with an alligator clip held on with a small hose clamp. It's gapped about .05.

I recommend the second method.

If you have fire, new gas and plugs.

Do simple first.

 

Ok after all the troubleshootin and wire chasin it turned out to be the battery. It had enough charge to turn the engine over nicely but not enough to energize whatever relay to give it spark! Charged up the battery overnight and she fires right up each time. Battery is only 2 years old so I hope I get another year or so out of it. Thanks for all the replies! Live and learn.....