Ktm 350 no spark

Is it turning over just not starting? Or are you getting nothing?

Yep Turns over, fuel pump seems to be working and spraying fine but, there is no spark when you pull the plug and touch it to the outside of the cylinder so it obviously wont start.

You tried disconnecting the killswitch? Iam not familiar with that model. Does it have neutral switch?

Have u checked fuses? The capacitors go bad and blow the fuse

ktm-5 wrote:

Have u checked fuses? The capacitors go bad and blow the fuse

Yes I disconnected the killswitch. I also tried starting my brothers with the killswitch on and it sparked at least once and then wouldn’t spark anymore.

Also checked all the fuses and even swapped that main fuse block set up off my brothers bike with no luck there either.

How about a new plug? Nevermind u already checked it. How about the grounds?

Yep confirmed my wire, coil and plug worked fine on another bike. Checked all the grounds I could see, the one under the seat by the battery and the one up under the gas tank.

Is the light behind number plate giving any codes?

Is the fuel line connected? Mine disconnected after a tip over and it was a pain discovering that That was the problem. It looked like it was connected, but a simple push and it clicked, voila bike back in action.

swtwtwtw wrote:

Is the fuel line connected? Mine disconnected after a tip over and it was a pain discovering that That was the problem. It looked like it was connected, but a simple push and it clicked, voila bike back in action.

Did that cause u to not have spark? He's having trouble getting spark

Maybe remove the tip over sensor.

Check all the grounds around the coil. Make sure there’s no paint and it’s true metal on metal.

No codes, fuel lines are in and tight and pumping. Checked that before I found the spark problem. Swapped top over sensors so it’s not that either. Grounds appear to be good, clean and tight everywhere.

If u have available another bike to swap parts with I'd try that one by one but it sounds like from everything you have checked and tried the stator took a shit. Had that on a kx 85 once, boy fell in a corner and bike stalled, wouldn't start, knew it was overdue for topend so did that no luck, swapped all electrical and nothing until I did the stator

Yea I mean theres on the stator, cdi and ecu so I'm thinking stator or cdi, I can't imagine the ecu would do this. I was wondering though, would this bike spark and run initially since it has a battery or not? Does the stator provide power directly to the spark plug or is it run through the battery first?

That I'm not sure of

I have a 2018 KTM 350 EXC-F. I have had multiple problems. I haven't had the bike off-road and don't ride it hard.
I have had to replace the whole wiring harness. The bike wouldn't turn over. It was dead. I unplugged the key switch and could jump it with a wire. A few weeks ago, the bike would crank over. But not start. I couldn't hear the fuel pump crank once I turned the key. Dropped it off at the shop and now the ECU has gone bad. It's been a nightmare. Wondering if I bought a lemon.

DannyE wrote:

I have a 2018 KTM 350 EXC-F. I have had multiple problems. I haven't had the bike off-road and don't ride it hard.
I have had to replace the whole wiring harness. The bike wouldn't turn over. It was dead. I unplugged the key switch and could jump it with a wire. A few weeks ago, the bike would crank over. But not start. I couldn't hear the fuel pump crank once I turned the key. Dropped it off at the shop and now the ECU has gone bad. It's been a nightmare. Wondering if I bought a lemon.

How many hours does it have on it, and did you do the wiring harness yourself? Mine was a bad ecu, they replaced it under warranty, the bike had 7 hours on it when it went out. Did you buy it new?

I purchased it brand new. Has right around 80 hrs on it.

80 hours, yea you're definitely out of warranty period regardless of how hard you've ridden it. Wiring hardness going bad on a bike isn't that uncommon but if you've had that many problems it could be stemming from something else. How long ago did you do the harness? Maybe it fried the ecu because they did my harness and ecu when it went.


I'd buy a vortex to replace that stocker. Your bike will run a million better and just keep your fingers crossed this is the last one.

Have you contacted your dealer? That's where I would start with that low hour count.

captmoto wrote:

Have you contacted your dealer? That's where I would start with that low hour count.

You talking to me or danny e? I'm assuming me because 80 hours does not seem low lol. But I did and they handled everything for me, ended up replacing the wiring harness and ecu, I think something shorted in the harness and took the ecu out in the process.

KTM covered the wiring harness and labor. KTM will cover the ECU but not labor. Comes out to around $220.00 for labor.

I think thats pretty damn solid for a bike with 80 hours. I wouldn't complain. If that was a jap bike, you'd be high and dry.

The connectors in the white plug behind the front number plate corrode and go bad. The bike eventually won't start, I've seen it happen on two 350sxfs so far. Not sure your exc has exactly the same connector there but I'll bet it does. Look for funky white residue inside that plug.

ob wrote:

The connectors in the white plug behind the front number plate corrode and go bad. The bike eventually won't start, I've seen it happen on two 350sxfs so far. Not sure your exc has exactly the same connector there but I'll bet it does. Look for funky white residue inside that plug.

KTM replaced the whole wiring harness. The issue was bigger than corroded connections.

When I got my bike back. I put heat shrink on all of the connections behind the front number plate.

Thank you for the feedback!

ob wrote:

The connectors in the white plug behind the front number plate corrode and go bad. The bike eventually won't start, I've seen it happen on two 350sxfs so far. Not sure your exc has exactly the same connector there but I'll bet it does. Look for funky white residue inside that plug.

DannyE wrote:

KTM replaced the whole wiring harness. The issue was bigger than corroded connections.

When I got my bike back. I put heat shrink on all of the connections behind the front number plate.

Thank you for the feedback!

Oh sorry didn't relize you got it fixed. ✌? but all it takes is one corroded connection to cause a no spark condition.