2002 Aprilia Mille 'very' intermittent stalling problem
Discussion
I honestly thought i'd fixed it.Bike starts great from cold everytime and continues to ride perfectly,however,right out of the blue,and this is the only time it does it is pootling along at 20mph in town it just smoothly just doesn't want to respond to throttle and if you pull over it won't idle,if you slip the clutch and keep the revs up you'll keep it going,bike is fine incidentally all up through the rev range,it's just at very low speed and it won't idle when fault occurs.
The faults i cured on the bike all at the one time were TPS was at -1',not '0' where it should be,throttle body mount rubbers were split/perished,vacuum line one way check valve was knackered,i replaced plugs and checked all vacuum lines,i also set the throttle bodies back to a suggested basic base setting.
Initially after i did all this i went on a 35 mile round trip to see how it would act,it was perfect!!Never missed a beat!
Next day after a few miles driving going along at 20mph i gently accelerated and felt the slight jerking(like your in 2 gears too high)and i instantly know it's happening again.
Fault always clears itself on the one journey ,it's never bad all day every day!It's annoying.Someone said his coil packs breaking down done this but my bike never splutters,jerks at higher revs,i hear coil packs can break down usually when they heat up and a connection seperates at 'any' point in the rev range,i'm not getting that.
Anyone help?Thanks.
The faults i cured on the bike all at the one time were TPS was at -1',not '0' where it should be,throttle body mount rubbers were split/perished,vacuum line one way check valve was knackered,i replaced plugs and checked all vacuum lines,i also set the throttle bodies back to a suggested basic base setting.
Initially after i did all this i went on a 35 mile round trip to see how it would act,it was perfect!!Never missed a beat!
Next day after a few miles driving going along at 20mph i gently accelerated and felt the slight jerking(like your in 2 gears too high)and i instantly know it's happening again.
Fault always clears itself on the one journey ,it's never bad all day every day!It's annoying.Someone said his coil packs breaking down done this but my bike never splutters,jerks at higher revs,i hear coil packs can break down usually when they heat up and a connection seperates at 'any' point in the rev range,i'm not getting that.
Anyone help?Thanks.
Jammez said:
I can't help with your fault finding but I can recommend AP workshops in Tamworth (depending on where you are in the world) there isn't much they don't know about Aprilia's and a thoroughly nice bunch of people too!
I'm on their facebook page! :-)Their too far away to pop in(hundreds of miles)Garages nearby me are terrible,and taking an i termittent fault to them they'll just start firing the parts cannon at it once they get their hands on it!Ap workshops are great though,heard nothing but good things about them.
My money is on the coils. With twin plugs, and, as I remember it, one coil per plug, it's quite easy to discount coils as both coils per cylinder need to give up at the same time for that pot to stop firing. Both on the same cylinder starting to break down and giving intermediate faults will result in some difficult to pin point issues.
2002 bike is probably due new fuel lines, complete clean of system, ultrasonic clean of injectors.
Other problems I've known on EFI bikes:
Sick fuel pump, low pressure or flow.
Fuel pump in tank stops due to overheating during slow riding. (low fuel level made it worse..,fuel warms up a bit..)
weak/dribbling injectors
Crank position sensor
Old, stale fuel.
Bad earth on ECU is a fun one, some Marelli ECUs have several dozen pins, none of which is actually a proper chassis earth ground, it relies on the mounting bolts.
My first effort at diagnostics might be the plugs, strobe the timing see if it's stable, maybe check fuel pressure (because I have a gauge and a T piece).
Then start research on any ECU diagnositcs. My Duc of similar era has a connector for this, but I've never had to go there.
Sometimes new injectors are cheap to try, proper cleaning is not expensive.
Other problems I've known on EFI bikes:
Sick fuel pump, low pressure or flow.
Fuel pump in tank stops due to overheating during slow riding. (low fuel level made it worse..,fuel warms up a bit..)
weak/dribbling injectors
Crank position sensor
Old, stale fuel.
Bad earth on ECU is a fun one, some Marelli ECUs have several dozen pins, none of which is actually a proper chassis earth ground, it relies on the mounting bolts.
My first effort at diagnostics might be the plugs, strobe the timing see if it's stable, maybe check fuel pressure (because I have a gauge and a T piece).
Then start research on any ECU diagnositcs. My Duc of similar era has a connector for this, but I've never had to go there.
Sometimes new injectors are cheap to try, proper cleaning is not expensive.
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