I have a 96 FLHTCUI that has a very hard problem to diagnose. About 30-40 minutes into a ride (never before), the engine will cut out for a few seconds and then return to full power and go on as normal. Sometimes this will happen 10 times on a 3 hour ride and sometimes it happens only once or not at all. I have a "Big Shot" fuel tuner attached (not the problem because it did the same thing before it was added) and when this problem occurs, the LED set indicates a call for strong acceleration to the injectors. I have tried to find a pattern but there is not a very distinct one that emerges but it is most likely to happen when the throttle has been steady and there is a reason to add power (climbing or speeding up). But that is not always the case. When it does happen the engine will begin to sputter and if I clutch it and drop the throttle it will die entirely. Or I can nurse it along through the sputters and it will pick up again and go on it's own. I can always restart the motor by clutching it and then after a few seconds (5-10) let the momentum restart it. Or if I am stopped, it will start again with no problem. I have checked and rechecked all of the connections. Now I am not sure where to go next. Any ideas??

 

Are you getting any codes?

 

The ECM shows no diagnostic codes stored. That is why I am so puzzled.

 

Gas tank not properly venting? Try a new gas cap?

 

Good idea, Thanks. I also had someone suggest that there may be something in the gas tank that blocks the intake on occasion. I will try and scope those problems and post the results.

 

When was the last time(if ever) the fuel filter was replaced? Could be that and wouldn't throw a code.

 

I would think the fuel filter is gone / water in the fuel / or a combo.

 

Are you losing electrical power when it cuts out? If so, suspect the ignition switch.

 

I checked the fuel cap and the vent works normally. The electrical system does not drop out when the motor acts up. It works normally throughout the sputtering problem. The bike only has 16,000 miles on it but it is possible I guess that the fuel filter is the problem as I know the bike sat unused for a significantg time in its life. I can order one and make that replacement to see if it solves the problem. I

 

When exactly did this problem start happening? Was it right after mods done to the bike such as handlebar swap, fuel tuner installed, etc.
Might help narrow the problem down for you.