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Discussion Starter #1
Ok so I'll try and get the whole story in here straight.
Bike was running pretty good prior to doing service. (Always been a little bit rough at low rpms which seems to be standard for these on factory mapping) And I must add that the last long run done on it, there was a bit of a vibration I had put down to road conditions when running along a back road at around 110Mph.
Did the service.
New oil & filter
New brake & clutch fluid.
Replaced fork oil. (Huge improvement! Had too much oil in there, plus who knows how old it was.)
Valve clearance check. All in spec although one only just, so left alone and put valve cover back on.
Took throttle bodies off to get valve cover off and managed to break an injector doing so. Replaced that.
Installed new fuel filter and in tank hoses.
Changed plugs to Iridiums NGK CR9EIX.
Reassembled it all and did a test run which seemed fairly good but maybe slightly rough at low revs and motor seemed to run a few degrees temp less than I would have expected for given air temp but smelled hot when I stopped back at home after around 90 miles of riding.
Next run I started by filling the tank again and thought it had used a little more than I would expect. Definitely running a bit rough at low revs and temp still looks low but exhaust seems hot and after 70- 80 miles definitely running rough/ missing below 2000 revs. after a couple of quick stops it then failed to start. Turned out the fuel filter hose had come off the pump. did a temp fix on this only to have it happen again 30 miles later. ( Turns out fuel hose wasn't actually submersible type).
Took bike home to sort. Put original fuel filter and hose back in ( New hose on order). Took bike for very short run and was developing a miss as soon as I left the driveway. even causing some missing & vibration at 5-6000 rpm. running pretty rough heading back into town the warmer it got.
Changed back to original spark plugs once it had cooled down, and went for a short run and began missing worse than ever, turning back into town it was missing and popping on decel and bogging on acceleration and rough across the range although I never revved her right out.
Engine temp seems possibly slightly cooler than normal, exhaust seems hot like cat is burning uncombusted fuel on it. Plugs all look too clean if anything, and all the same, had thought I might find a dirty one meaning a dud plug or coil on that cylinder but no!
Have it apart again looking for loose/disconnected plugs, jammed pipes etc, but can't see anything so I'm looking for suggestions.
Initial logic would be something I have done, but that may not be true as it seems to be getting worse!
:banghead:
 

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Is it possible the fuel pump is bad...
 

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Or that injector you replaced is not correct? I would look closely at the injector connections. Actually, look at ALL the electrical connections.

It won't be mechanical. Do you have the VDST software and cable? You may find a Detected Trouble Code in the ECU (there is no "Check Engine" or MIL light on your bike).
 

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Discussion Starter #4
Where is the best place to get hands on a cable & VSDT software?
Have had a good look at connections and can't see anything obvious. although injector connectors area real pig to get at hence the one I broke! Replaced with identical unit.
All header pipes seem to be around same temp as they warm up.
Fuel pump appears to work ok in that it does run and build pressure as you can hear at startup.
 

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Not sure the VDST is available for sale anymore.

I do think some fellow Kiwis might have one you could borrow??? Ask @The_castle ....he might know.
 

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Damn, you folks make this complicated........
Techno Research used to make the VDST
Their new version is called Alaris........no cables, it's Bluetooth
It works with your 5SM ECU

Before you buy one......you have a 12 year old bike with rubber hose problems.......
Go to the hardware store and buy 8, 4Mx25mm Allen head screws and a 3mm ball end screwdriver
And change the manifold clamp screws
Buy 4 vacuum caps to fit the brass nipples on the throttle bodies

You have air leaks......
Your plugs are too light
You have new plugs
Your fuel pump works
What's left?........Too much air:wink2:
 

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Discussion Starter #8
Sorry forgot something minor ( Knew I would) already replaced the rubbish phillips head screws on the throttle body manifolds with nice S/Steel allen heads. (So much easier to deal with).
So Noel you are suggesting capping the trottle balancing tubes at the throttle bodies to eliminate them as a potential air leak source?
Thanks Andrew
 

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So Noel you are suggesting capping the trottle balancing tubes at the throttle bodies to eliminate them as a potential air leak source?
Thanks Andrew

Or replace the hoses that lead to the sides of the bike and replace those vacuum caps....makes checking throttle body synch much easier.

Or do you have an evap system still in place?? (Euro4 and all US bikes)
 

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Discussion Starter #10
Nope no evap system thank goodness!
 

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Nope no evap system thank goodness!
Then Look at the 4 rubber caps on either side of the frame (put there to enable easy throttle synch). They are infamous for perishing.

Just head to auto parts store for some 4 mm vacuum caps....and insect the rubber hoses that lead from them to the intake manifolds. Or just replace those too.
 

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Rough Running

I have the same basic model and the same age. I had the same problem. Someone suggested a fuel pump and they are right. The hoses turned to goo and it was sucked into the fuel pump. Replace all the hoses with the correct type. New fuel filter and pump. It will run normal again. Your making it harder than it needs to be.
 

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Discussion Starter #13
Ok so this is where I have got to so far.

Rechecked all the hoses and vacuum caps etc. All look to be in good condition.( No auto parts store worth a pinch of anything within 100 miles of here. Heck the clown at the local M.Bike shop had no idea what the deal was with fuel injection hose let alone submersible).
Rechecked all the throttle body manifolds and all ok.

Working through the manual in the Air intake injection section. What a pain in the butt!
I can only find instruction on testing earlier type ignition coils not the later stick type Bera coils!
Thought I had nailed it with a faulty air temp sensor only to find the manual appears to show the wrong pins to check (D-C) as the reading was way off the scale until I checked against the wiring diagram and colour code against the wiring on the bike itself. The Kohm reading was good across pins a-b ( V/Blk & Y/Pk).

I like Tuna's idea regarding the fuel pump, except I only changed the original fuel hoses as a precaution as recommended on here & in the manual, while changing the fuel filter. The hoses appeared to still be in good condition ( We have very little ethanol fuel here) and they have been reinstalled with the original filter while I was waiting for the second piece of fuel line to turn up after the incorrect type turned up the first time. Fuel pump must still be working as the first change of fuel hose got pushed off the pump and with the hose off in the tank, fuel could be seen swirling around inside.Is it possible something has come out of the hose between the filter & the injectors causing a partial blockage in these? When the incorrect fuel hose first came off it looked a bit dodgy on the inside like had delaminated slightly around the pump hose barb like the internal fuel proof barrier had started to lift off.
Does anyone know what the actual voltage of the coil pulse for the injectors is as this should allow them to be jar/flow checked.
 

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The coils for your bike...which I think is a 2008/9 F4 1078 (sure would be nice to have that information in your signature line)...is 12 volts. They are actuated when grounded by the ECU.

Chasing Electrical Gremlins is tough.

If you would like to have the use of my VDST tool, I can send it to you for postage as long as you return it in good condition or replace it with the new VDST tool.
 

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ON temperatures: You can't really estimate temperatures with eyes/hands/feel, you must measure. You can get an inexpensive infrared temp gun and then you can directly see if you have a "cold" cylinder or a "hot" exhaust.
 

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Discussion Starter #16
Hi Guys.
Thanks for all the info, I am going back to the garage to do some more checks and testing when time permits as I have a heavy workload at present getting in the way of the important things in life! I will pop back as time permits to relay anything I find.
I love the way people help on this forum and have looked at many similar threads to this but have developed a real dislike for people not finishing the thread with a result, which therefore makes that thread near useless so I will endeavour to keep you all informed as I go. So if you don't get regular updates for a bit I apologise now.
Cheers Andrew
 

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Popping on decel, fuel problem (lack of). Need to find a way of checking the volume of fuel being supplied over a sustained amount of time, say more than 30 seconds. You could also plumb in a manual fuel gauge and watch pressure under shstained high rpm to watch for pressure drop.
 

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Discussion Starter #18
Yep next plan is probably to pull the fuel injectors and test, then slip in a pressure gauge in the fuel line and go for a ride.
Pulled all the coils and cranked over motor with plugs in them and had regular spark on each but remember this gets rough as it warms up so doesn't entirely eliminate them as they were cold. Would be good if they could be tested off the bike then they could be preheated before testing.
 

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Discussion Starter #19
OK, finally back to it.
I tried the coils by putting plugs in them and cranking bike over as I can't find a way to test them off the bike and all seemed to fire the plugs ok. Put the coils back in and reassembled bike minus fairings and went for a short run. Rough as, even from the start. ( Remember I have used two sets of plugs so I'm thinking they are ok.) Short run and home and went a step further than Silent Service suggested with the spot laser temp gun ( Which is what I used before, but only at idle) and dragged out a full Flir thermal imaging camera from work. Everything looked pretty even at idle given that the two center pipes run a little hotter than the outside ones probably due to air flow restrictions. Held the bike at 2500 Rpm's for a minute and then all pipes ran nice and hot except No.1 which dropped drastically in temp as the motor misfired like a pig! I'm thinking coil breaking down so will swap 1 & 2 over once things cool down enough to get in there, and we'll see what changes.
 

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Good idea swapping coils,that will tell you straight away if it is a coil problem.Good luck.
 
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