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Discussion Starter #1
ok. since my first ride of the season, i have been plagued by my bike not wanting to start after i ride it. it has started about 20% of the time from hitting the start button, but it has gotten progressively worse. i can't figure it to be a mechanical problem, but then again, i can't figure out WHAT it is.

it will always "first" start when i pull it out of the garage. it idles fine, runs fine, acclerates fine and runs like a new bike. if i have to stop and turn the bike off for any reason...like maybe GET GAS, 80% of the time it will not start. what it will do is try and fire up, then it will die and will not start past that point without waiting for a while. while trying to use the start button i can smell the strong smell of gas, i,e. flooding. wait a little while, then it will fire up and all is golden till i have to turn it off again.

now, even though it will not start with the start button, i can pop start it if i have a good enough hill. once it starts, a plume of black smoke comes out the pipes furthering my "flooding theory", then again...all is well until i have to turn it off again. this is 80% of the time, because sometimes it will start using the button. it has been such a PITA i have studied this and it has gotten worse. i even notice after a hard run, without turning it off, the bike will idle a little higher than normal. this lets me believe it is being told to dump too much fuel and i'm sure if i cut if off at that point, it would not start. of course this thing really sucks especially if i haven't ridden in a week because after constant use of the starter to try to get it started, it will drain the battery down.

yesterday, the bike started up when i pulled it out from last weekend. idled fine for about 5min while i got ready. rode fine, even pulled a power wheelie. then the gas light came on. stopped to get gas, hit the start button...the bike fired up, idled a little high for 30sec, then choked off. after that...no start. no pop start, no nothing. i even went to the extent to try starter fluid, which the bike ran then would start, run, rev, until the fluid burned off. then nothing.

i think it's the PCIII...maybe a loose wire, or something...TPS, i don't know. i have ruled out a leaky injector because it's too inconsistant. i have ruled out fuel filter because once started the bike runs perfectly. i don't know if there is a "starting fuel cycle" or what, but that is the only time i have a problem. i have a dyno session tomorrow and hope that something is found out. but now i have to get it running first to get it down there. i plan on stripping it down tonight.

i remember a thread a long while ago about some part (electrical/mechanical) that if fails, it will not start. after that long agonizing read...any ideas?
 

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I recently had the problem with mine sometimes not wanting to start again after being ridden...turned out to be poor contact in starter button. The mechanic cleaned it up and was surprised to have see this level of wear in such a new bike.
 

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If it was the wire from the throttle pot to the PC it would run very odd and inject the same added % fuel in for all the points, the PC gets its power from the injection and earth from where ever, it won't run at all if the earth is not made, my thoughts are disconnect the PC and try it, also check the contacts in the plug to the engine temp sensor-----its the one around the water outlet by the thermostat, if thats gone dicky it will run full start enrichment all the time, a modern ecu would know it had been running for 10minutes and would automatically put in a "running" value, I don't think this old magnetti ecu is clever enough to do that........

It also gets an enrichment signal from the starter motor, which may explain why you can bump start it.
 

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Nothing to add but considering the strange behaviour with some of the reports on PCIII and melting/internal damage in our undertray I'd definitely be removing that first, as suggested above.

Just to check; you don't hear just CLUNK, or it sort of catches but doesn't really turn over but then will catch on 2nd/3rd try? Sounds more electrical or fuel than feeling mechanical?
 

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damn, that's a tough one.
i like mike's advice. take out the PC.

from what you wrote, i does not read like you have a fuel delivery problem. or a problem with the spark generation (it runs with the starter fluid).

it reads like metering - somehow the fuel delivery is not right at startup. like it's way too rich. basically, the bike thinks it's cold even when the engine is warm.

alex
 

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I used to have this problem in my 71 beetle. Ran perfect, started perfect on 1st start up, idled fine. But the damn thing would NOT start hot. I replaced EVERYTHING and the only saving grace that MADE it start was a DIS system, that would start "in under even the crappiest conditions" (as stated by the manufacturer) with 100X more voltage than the stock system. And even then, it would be a moderate start if the motor was warm.... :wtf:

I would like to hear the solution to this issue. Could be synced TBs? My bug ran nearly the same after the sync, but it started a little easier after the sync.
 

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Discussion Starter #7
re: starter button...it can't be that. because the start button always works, and always turns the motor over.

mike, you seem to be dead on. that's where i'm targeting my search. especially since i thought i may have had temp issues with late fans coming on. i just wasn't sure if there was a "startup enrichment" signal. because the motor is dead cold when i pull it out the garage, is probably why the over rich condition doesn't occur. but once the ECU needs to have a correct value after it warms up that may explain it. i will try and locate the ground and disconnect the PC. if that doesn't do it, then i will check the temp switch. i hope the ducati shop where i'm taking it would have a new one if i needed it.

i don't think it's something mechanical. especially since it runs so well after it does start. it is a little odd that it won't continue to run after the starter fluid got it going, which i'm not going to use anymore because of how lean it makes the motor run. ie. MAJOR engine knock. i just wanted to see if it was getting spark and such.

when i get home, i will try and start it, but i have a feeling it won't start. i'll solve the problem tonight and post. i was even considering swapping the WCT chip out and replacing it with the RG3 eprom, but that's even desperate as cold engine or not once it's running it's fine.
 

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style_one said:
re: starter button...it can't be that. because the start button always works, and always turns the motor over.

mike, you seem to be dead on. that's where i'm targeting my search. especially since i thought i may have had temp issues with late fans coming on. i just wasn't sure if there was a "startup enrichment" signal. because the motor is dead cold when i pull it out the garage, is probably why the over rich condition doesn't occur. but once the ECU needs to have a correct value after it warms up that may explain it. i will try and locate the ground and disconnect the PC. if that doesn't do it, then i will check the temp switch. i hope the ducati shop where i'm taking it would have a new one if i needed it.

i don't think it's something mechanical. especially since it runs so well after it does start. it is a little odd that it won't continue to run after the starter fluid got it going, which i'm not going to use anymore because of how lean it makes the motor run. ie. MAJOR engine knock. i just wanted to see if it was getting spark and such.

when i get home, i will try and start it, but i have a feeling it won't start. i'll solve the problem tonight and post. i was even considering swapping the WCT chip out and replacing it with the RG3 eprom, but that's even desperate as cold engine or not once it's running it's fine.
Ah!!!!!!!!!! fans, I forgot that one, the two clues now tie up, its the engine temp sensor telling the ecu its cold, hence no fans and too much fuel when warm, try swapping the connecting plugs over from the one on the rad to the one in the head and see if it will start then, you will also then be able to read on the dash the temperature the engine sensor is sending to the ecu..........

Also the only way to disconnect the PC is to swap all the injector plugs back to std, removing the earth wire will just kill it dead.
 

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Discussion Starter #9
hmmm, i've been trying to figure out what could go wrong after a winter sit. a temp switch could do it. i'm going to try and see what i can do. i'll also see if the two switches are interchangeable. if they are, and it starts after the swap i can always order a new one for the temp in the dash. don't need that to work properly to ride it.

let's hope for the best then for this eve. thanks for everyones input. i'll report later.
 

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Discussion Starter #10
Update

well, i found out why it wouldn't start at all from sunday. pulled the airbox and opened the throttle body, turned the starter and saw no fuel spraying into the combustion chamber. when i unhooked the tank no fuel leak. pulled out the fuel pump and viola! the hose coming off the fuel pump that leads to the filter was dangling in the tank! :shocker: now, how could this happen? well, everybody's favorite eastcoast dealer put on a new fuel filter at my 7500mi service. they didn't put the hose on good. in fact, the clamp was still on the end of the hose. :mad: i hate those clamps so i didn't want to deal with them, but i was able to work the hose on the fuel pump. once it was on there it did not want to come off, which leads me to believe it couldn't have come off by fuel pressure alone. it just wasn't put on properly. in addition to that, the fuel filter has an arrow on the side of it, but it's pointing AGAINST the flow of gas from the pump! as in put on backwards! now, i'm assuming because after it was put on they dynoed it, test rode it, and i rode it from philly to DC, and it runs fine when running that maybe the fuel filter is NOT unidirectional, but it is odd.

so i was happy i found this problem, BUT on reinstalling the fuel pump the o-ring seal got pinched and broke. :cussing: of course this was at 1am, so i'm going to have to cancel my dyno/remap session today. i'm going to order 2 o-rings and 2 new temperature senders and overnight them. i think all in all that my bike was suffering from the temp sender to the ecu, and then this fuel pump hose . so i may end up solving all the problems without needing a remap. once i get it running again i am tempted to get another map done though because if the fuel pump hose wasn't put on good, how do i know the map was done as good as it could have been.
 

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excellent work! glad to see that you found the source of your bike's ills.

was the work done by an "authorized" mv dealer?

i wonder how many other here have had experiences where the "pro" mechanics actually do such poor work that the bike is in worse shape than when we bring it to them.

i have had this experience with a honda.

and that was the last time ANY of my bikes have been to a dealer for service.

i'm not trying to say that all dealer service centers are bad, but when you see the results of stuff like this, it really makes you think for a bit.

alex
 

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style_one said:
well i hated to say it, but it's the truth....i took it to Fast by Ferracci
Glad you got it resolved, but man FBF seem to get worse (Although I have never had experience with them)
 

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I have nothing good or nice to say about FBF! :flickoff: and i will leave it at that. i am pushing for your problem to be solved by the temp sensors and getting that hose on right. Now we can go out and test it and take some nice riding vids.
 

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Discussion Starter #15
Update

bike is running back to normal, which is great. nice plumes of backfire after hard throttle. :smoking:

i think i still will get a map done, because i get the occassional backfire in the intake which started after i took it to get the service/PCIII/filter/dyno done. outside of that, turned out it was the temp sender to the ECU. now the fans come on in the low 200's (felt them at 202). i'm in love all over again!!

thanks guys...and chris, you'll be hearing from me. :naughty:
 
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