What are the symptoms of a faulty ECU in an EFI motorcycle?

[Victor]

When the ECU of an EFI motorcycle is damaged, the vehicle may exhibit the following symptoms: Failure to start: A damaged ECU can directly prevent the motorcycle from starting. Fuel pump operates but does not inject fuel: When the motorcycle's ECU is damaged, the fuel pump may work normally without injecting fuel in the non-ignition state, and the fuel pump relay appears to be in a normal engaged state. No fuel injection during ignition: Even if the owner starts the motorcycle when the ECU is damaged, the vehicle is in an ignition state but still cannot inject fuel. This situation is due to an internal program fault in the ECU, which will prevent the motorcycle from running normally.

[NovaMarie]

That time when the ECU of my fuel-injected motorcycle broke down really gave me a headache—at first, the start button didn’t respond at all, the battery had power but it just wouldn’t ignite. After several hard pushes, it barely started, and while riding, the power was sluggish, acceleration felt like a snail climbing a hill, especially on the highway where the bike jerked intermittently, shaking so much my hands went numb. At idle, the RPM fluctuated wildly, sometimes jumping to 3000 RPM and then dropping to 1000 RPM, the body swaying like a cradle, and fuel consumption skyrocketed—normally a full tank lasted a week, but now it was almost empty in two days. The malfunction indicator light stayed on, and I thought it was a minor issue, but a simple check of fuses and plugs didn’t help. When I pushed it to the repair shop, the mechanic diagnosed it as an internal short circuit in the ECU. That thing is the bike’s computer, controlling fuel injection and ignition—once it fails, the whole system goes haywire. I learned my lesson: don’t let the ECU get wet when washing the bike, and regular maintenance can extend its lifespan by a few years.

[LeStella]

I've been riding my EFI motorcycle to commute for years, but that time when the ECU malfunctioned completely disrupted my routine—it wouldn't start in the morning when I turned the key, the engine just cranked without firing. After struggling for five minutes, it barely started, only to run sluggishly on the road. At a red light, the engine suddenly stalled, giving me a real scare. The idle speed fluctuated wildly, causing slight body shakes, and fuel consumption jumped from the usual 3 liters per 100 km to over 5 liters. The dashboard warning light stayed on the whole time. It was frustrating—what's normally a 15-minute commute turned into being half an hour late. Finally, I took it to the 4S shop, and replacing the ECU assembly fixed the issue. The ECU manages the engine's core functions; when it fails, it not only affects performance but also increases safety risks. Fellow riders, pay attention to unusual noises during daily rides and get your bike checked promptly—don't delay.

[WalterMarie]

When the ECU of my fuel-injected motorcycle failed, the symptoms were super obvious—pressing the start button had no effect at all, the battery was fine but the bike just wouldn't ignite; after starting, the acceleration was weak during riding, struggling even on small slopes, and the RPM jumped erratically at idle, making the bike unstable. Fuel consumption increased, and the malfunction indicator light stayed on, warning me. I immediately recorded a video and sent it to my friends, who said the ECU is the brain—if it fails, the entire control system goes haywire, and it's best to get it repaired promptly.