Hi any ideas on 09 fatbob 5000klm runs erratic occasionally like it has a fuel blockage but the electrics become erratic as well it coughs and splutters for somtimes half an hour then runs like a dream under different circumstances each time 2up on my own hot day cold day has happened maybey a dozen times but doesnt show on diagnostics any ideas or anynone had the same problem

Thanx

Greg M

 First up sounds like a loose wire/connection/terminal if it's erratic like you describe.

(If you've got a proximity security fob, make sure the battery is up to scratch.)

Time for the old wriggle the wiring harness while she's running trick to see if you can isolate the area.

It's not likely that the spark plugs or HT leads are causing an erratic problem, possible, but not likely. 

Battery terminals and Crankshaft position sensor would be first to check followed by the fuse block and then the rest of the harness.

Intermittent open circuits can be caused by dry joints, broken wires or corrosion, so they'e bitches to find most times.

If you're not blowing fuses, then the chances of a short circuit are very slim.

If you can't get the problem to replicate by frigging with all of the above, then it may indicate that there is a component problem that's got to be diagnosed.

Good luck, hope you find the gremlin.

Thanx Rider & Scotty will have a good hard look at your suggestions when it comes back from the shop if they dont sort it.

Hi greg, mate have your workshop check out the VSS(vehicle speed sensor), my '07 Fatty done the same thing out of the blue, i had the fuel management system changed, didn't fix the prob', i got the phone call today saying it's going like a train again. My speedo was erratic and the blinkers wouldn't self cancel, idle erratic and run like a busted arsehole. I'm no mechanic, but it sounds like a similar problem you are having.

cheers mick will get them to check that as well so far no luck