Ducati.ms - The Ultimate Ducati Forum banner
  • Hey Everyone! Vote for the Site Favourite BOTM winner for the year of 2022 HERE!

2007 ST3 Gremlins

584 Views 11 Replies 7 Participants Last post by  stoshmonster
Hi all.....
Totally at a loss with my ST3s. Parked it after riding in the summer heat and couldn’t start it again.Would crank. But no luck. After about an hour it started no probs so managed to get it to my mechanic. After a full service including belts etc....same problem.
Back to mechanic,replaced fuel pump relay and new fuel pump. Ran it to 103C as the fan cut in...no problems. Took it out for a long ride, after about 20 minutes it stalled again and it took a wait of about 5 minutes to restart. Stalled again on the way back to the mechanics and pushed the the rest of the way. Started again after a while again no problems. Any suggestions as to the fault. All suggestions greatly appreciated 🤔
1 - 12 of 12 Posts

· Just Visiting Your Planet
Joined
·
12,257 Posts
Go through the checklist. You need air, fuel, and spark. Start with the easy stuff. Check the air filter and inlets for blockage. Check that the plugs are working as they should. Swap the two relays under the seat around and see if you might have a bad injection relay.
 

· Registered
Joined
·
199 Posts
Check and see what the battery reads right now. Across the battery posts read 12.8v being Ideal sitting for days. 12.6v and below, battery needs a charge. Battery is how old? Battery was charged during it sitting?
 

· Registered
Joined
·
7 Posts
Discussion Starter · #5 ·
Thanks guys, Plugs replaced and air filter too with service. Relay replaced along with the fuel pump. When the bike goes it’s great......it’s the intermittent problem that’s the worry When not starting normal power to the dash....It cranks fine and I think there’s power to the fuel pump. I have replaced the battery as well
 

· Registered
Joined
·
7 Posts
Discussion Starter · #10 ·
Thanks a heap guys,
Belter, I now know that the fuel pump is working.... I hear it every time I crank it over. That could have been the problem.
Following the crank position sensor feed, it sounds exactly what I’m experiencing
Will check it out
Regards everyone
 

· Registered
Joined
·
7 Posts
Discussion Starter · #11 ·
Fuel lines are in good shape apparently as they were inspected when the pump was replaced.
I rang a stealership and they said that bikes of my era don’t necessarily throw up codes
Anyone have the same problem?
 

· Average Weird Guy.
Joined
·
1,426 Posts
Anyone have the same problem?
Yeah I had something similar happen on my '95 900SS Warwick. Bike would just stall for no apparent reason and refuse to start. Wait maybe 15-20 minutes and the bike would fire up no problem.
One day after the bike stalled I opened the gas cap and heard a loud whoosh of in rushing air. Hit the key and the bike fired right up.
Turned out that the oneway inline check valve in my fuel tank breather hose was sticking and causing a vacuum to build up inside my fuel tank that was starving the carbs of fuel.
A pinched or collapsed tank breather hose or a clogged tank breather system will cause the same issue.
 
1 - 12 of 12 Posts
Top