Forums 🚥 PiT STOP 🔧 Hyosung Technical Help GD250N – Hanging Revs and Stalling when Throttle opened quickly Reply To: GD250N – Hanging Revs and Stalling when Throttle opened quickly
Alright!
I’ve checked for a vacuum leak, seems tight! no changes when spraying with brake cleaner! (didn’t have carb cleaner on hand, but I think it oughtn’t make a difference)
I’m thinking it might be the ISC malfunctioning somehow, it was running at somewhere between 1.5 – 3k revs depending on how it was feeling. I might try plugging the ISC air passage and using the idle adjuster screw to get it to idle and then checking again for hanging revs. If the ISC valve is permanently open, it would be equivalent to a vacuum leak (I think). I’ll let you know once I get around to doing that.
What I did notice today, is the first error code. I got a P0230 after running the engine for a while with it misfiring a couple times and checking the codes (got no codes before, even when checking). According to the service manual, P0230 indicates low voltage or open on the fuel pump relay circuit. I did switch out the kickstand switch relay and fuel pump relay and the issues persisted, so I’m not sure if the fuel pump isn’t getting enough power or something? I can hear it clearly when turning on the bike and it has never starved on me at high rpm or anything, so let me know if you have an idea.
Oh, and I did check just the battery, seems to be in decent enough shape (12.7V after several starts and stalls and without me ever putting it on a charger since getting the thing) I think it’s new, the owner probably replaced it before getting it inspected for road approval.