M620 running ric

pooh · 12-06-2017, 09:40 AM

Hi folks
I've got a problem with the wife's 2004 620, it runs really rich at low rpm and pops back into the air box. The exhaust tips are thick soot.
So far I've changed the following air filter, injectors, throttle bodies, temp sensor, ignition coils, plugs.

I've also checked valve clearances, cam timing etc does anybody have any ideas as she's getting fed up of not being able to ride it. It can be ridden but can catch you out in corners when the engine splutters and it's also dodgy when pulling out of junctions.

Any ideas will be gratefully accepted.

Thanks
Ian

slob · 13-06-2017, 07:11 AM

Get it down to a dealer, or someone else with the right diagnostic kit, and get them to check the fuelling with a gas analyser, may just want a quick ECU tweak. Have you balanced the throttle bodies and adjusted the air bleeds since swapping them out? Could also be an issue with the air pressure sensor on the headlight bracket.

pooh · 13-06-2017, 09:33 AM

Slob
The problem was there with the old throttle bodies but agree will need doing but don't think it's the route cause. I am waiting for ducatidiag and plugs to arrive to see if I have inputs from the various sensors. Don't suppose you have a temperature resistance chart for the temp sensors used by any chance?

Regards

Ian

slob · 13-06-2017, 05:54 PM

Sadly not, the book just says plug into DDS to test, might be worth an hour at Moto Italia for access to their factory diagnostics

pooh · 13-06-2017, 06:23 PM

I have plugged in to Ducatidiag today and air temp and atmospheric pressure seem Ok engine temp seems ok throttle position sensor is ok as well. I have checked injectors for leakage and operation all ok. I am running out of ideas and can't get it into Italian until the 8 th July and that was booked in three weeks ago. Phil the boss there had a listen the other day and thought it was a tight exhaust valve causing the popping back but there spot on in the middle of the tolerances. Her who must be obayed is getting fed up because she can't ride it due to it spluttering at the most in opportune moments i.e. Half way round a bend when you wind the power on.

Hey ho well see what happens.

Ian

Mr Gazza · 13-06-2017, 07:11 PM

If the fuel return pipe is obstructed it will cause too much pressure in the fuel rail and the regulator will be unable to deal with it. This will cause rich mixture. Especially at lower revs/throttle openings, as less pressure will be naturally relieved by the injectors due to the low fuel demand.
It could also be a fuel regulator fault? Although that would be rare as the pressure is pre-set by the poundage of the spring.. Not sure what would have to go wrong with it for the pressure to rise at low throttle settings.. I suppose it's possible to just stick?

It's hard to imagine why or how the return pipe could block up, but Hairyaxeman recently brought his S4 tank over with badly blocked vent and drain tubes.
We managed to get a piece of wire down one and partially down the other. He took it home and was successful in getting ever thicker guitar strings the whole way through the pipes.

What was surprising to find though, was that the return pipe was blocked solid. After some research and lots of help from the UKMOC elves, we discovered that there was nothing vulnerable on the inside end of the pipe, and he gave it large with various harsh rodding implements and got it clear.

Any help?

pooh · 13-06-2017, 07:36 PM

Gasa
Checked return pipes and swapped the pump assembly with the one off my monster so hopefully that rules that out. Getting to the point that half a gallon of petrol and a box of matches may be the answer.

Ian

Mr Gazza · 13-06-2017, 10:07 PM

Okay, but I can't see the pump delivering too much pressure.

Did you check the return pipe right from the regulator end with the rubber tube attached to the tank?

Seems like you have been most thorough though. I think that only leaves the regulator. Can you check that by substitution too?

pooh · 13-06-2017, 10:17 PM

Gasa
It's got a plastic tank on it and the regulator is part of the pump assembly which has been changed so uck knows what's going on. Both injectors are sealing and injecting when told to so their ok. Only thing it possibly could be is a dodgy crank position sensor which is the only part I haven't got a spare to try.

Ian

slob · 13-06-2017, 10:20 PM

Have you got access to a gas analyser? What CO readings are you getting in the exhaust? If you know this you can make meaningful adjustments to the ECU

pooh · 13-06-2017, 10:56 PM

Not at the moment but next on shopping list

Ian

hh93 · 20-03-2019, 11:58 AM

was this ever resolved ??

pooh · 15-05-2023, 04:53 PM

No Still playing up runs OK sometimes then like a beg of crap. Not been used recently due to wife damaging her leg but now want it sorting. Could it be crank position sensor issue as very intermittent.

adie851 · 15-05-2023, 05:18 PM

does it ever run on only one cylinder , when it splutters ... or does it always run on both ?

12-06-2017, 09:40 AM	#1
pooh Lincolnshire Area Rep Join Date: Oct 2002 Location: Grimsby Bike: M900ie Posts: 469	M620 running ric Hi folks I've got a problem with the wife's 2004 620, it runs really rich at low rpm and pops back into the air box. The exhaust tips are thick soot. So far I've changed the following air filter, injectors, throttle bodies, temp sensor, ignition coils, plugs. I've also checked valve clearances, cam timing etc does anybody have any ideas as she's getting fed up of not being able to ride it. It can be ridden but can catch you out in corners when the engine splutters and it's also dodgy when pulling out of junctions. Any ideas will be gratefully accepted. Thanks Ian __________________ Slighty less brain cells than I was born with

13-06-2017, 09:33 AM	#3
pooh Lincolnshire Area Rep Join Date: Oct 2002 Location: Grimsby Bike: M900ie Posts: 469	Slob The problem was there with the old throttle bodies but agree will need doing but don't think it's the route cause. I am waiting for ducatidiag and plugs to arrive to see if I have inputs from the various sensors. Don't suppose you have a temperature resistance chart for the temp sensors used by any chance? Regards Ian __________________ Slighty less brain cells than I was born with

13-06-2017, 06:23 PM	#5
pooh Lincolnshire Area Rep Join Date: Oct 2002 Location: Grimsby Bike: M900ie Posts: 469	I have plugged in to Ducatidiag today and air temp and atmospheric pressure seem Ok engine temp seems ok throttle position sensor is ok as well. I have checked injectors for leakage and operation all ok. I am running out of ideas and can't get it into Italian until the 8 th July and that was booked in three weeks ago. Phil the boss there had a listen the other day and thought it was a tight exhaust valve causing the popping back but there spot on in the middle of the tolerances. Her who must be obayed is getting fed up because she can't ride it due to it spluttering at the most in opportune moments i.e. Half way round a bend when you wind the power on. Hey ho well see what happens. Ian __________________ Slighty less brain cells than I was born with

13-06-2017, 07:11 PM	#6
Mr Gazza Lord of the Rings Join Date: May 2013 Location: Norwich Bike: M900sie Posts: 5,792	If the fuel return pipe is obstructed it will cause too much pressure in the fuel rail and the regulator will be unable to deal with it. This will cause rich mixture. Especially at lower revs/throttle openings, as less pressure will be naturally relieved by the injectors due to the low fuel demand. It could also be a fuel regulator fault? Although that would be rare as the pressure is pre-set by the poundage of the spring.. Not sure what would have to go wrong with it for the pressure to rise at low throttle settings.. I suppose it's possible to just stick? It's hard to imagine why or how the return pipe could block up, but Hairyaxeman recently brought his S4 tank over with badly blocked vent and drain tubes. We managed to get a piece of wire down one and partially down the other. He took it home and was successful in getting ever thicker guitar strings the whole way through the pipes. What was surprising to find though, was that the return pipe was blocked solid. After some research and lots of help from the UKMOC elves, we discovered that there was nothing vulnerable on the inside end of the pipe, and he gave it large with various harsh rodding implements and got it clear. Any help? __________________

13-06-2017, 07:36 PM	#7
pooh Lincolnshire Area Rep Join Date: Oct 2002 Location: Grimsby Bike: M900ie Posts: 469	Gasa Checked return pipes and swapped the pump assembly with the one off my monster so hopefully that rules that out. Getting to the point that half a gallon of petrol and a box of matches may be the answer. Ian __________________ Slighty less brain cells than I was born with

13-06-2017, 07:11 AM	#2
slob . Join Date: Jul 2003 Location: East London Bike: Multiple Monsters Posts: 9,707	Get it down to a dealer, or someone else with the right diagnostic kit, and get them to check the fuelling with a gas analyser, may just want a quick ECU tweak. Have you balanced the throttle bodies and adjusted the air bleeds since swapping them out? Could also be an issue with the air pressure sensor on the headlight bracket.

13-06-2017, 05:54 PM	#4
slob . Join Date: Jul 2003 Location: East London Bike: Multiple Monsters Posts: 9,707	Sadly not, the book just says plug into DDS to test, might be worth an hour at Moto Italia for access to their factory diagnostics

13-06-2017, 10:07 PM	#8
Mr Gazza Lord of the Rings Join Date: May 2013 Location: Norwich Bike: M900sie Posts: 5,792	Okay, but I can't see the pump delivering too much pressure. Did you check the return pipe right from the regulator end with the rubber tube attached to the tank? Seems like you have been most thorough though. I think that only leaves the regulator. Can you check that by substitution too? __________________

13-06-2017, 10:17 PM	#9
pooh Lincolnshire Area Rep Join Date: Oct 2002 Location: Grimsby Bike: M900ie Posts: 469	Gasa It's got a plastic tank on it and the regulator is part of the pump assembly which has been changed so uck knows what's going on. Both injectors are sealing and injecting when told to so their ok. Only thing it possibly could be is a dodgy crank position sensor which is the only part I haven't got a spare to try. Ian __________________ Slighty less brain cells than I was born with

13-06-2017, 10:20 PM	#10
slob . Join Date: Jul 2003 Location: East London Bike: Multiple Monsters Posts: 9,707	Have you got access to a gas analyser? What CO readings are you getting in the exhaust? If you know this you can make meaningful adjustments to the ECU

13-06-2017, 10:56 PM	#11
pooh Lincolnshire Area Rep Join Date: Oct 2002 Location: Grimsby Bike: M900ie Posts: 469	Not at the moment but next on shopping list Ian __________________ Slighty less brain cells than I was born with

20-03-2019, 11:58 AM	#12
hh93 Member Join Date: Jul 2018 Location: Lincoln Bike: M620ie Posts: 116	was this ever resolved ??

15-05-2023, 04:53 PM	#13
pooh Lincolnshire Area Rep Join Date: Oct 2002 Location: Grimsby Bike: M900ie Posts: 469	No Still playing up runs OK sometimes then like a beg of crap. Not been used recently due to wife damaging her leg but now want it sorting. Could it be crank position sensor issue as very intermittent. __________________ Slighty less brain cells than I was born with

15-05-2023, 05:18 PM	#14
adie851 Member Join Date: Jan 2015 Bike: S4r Posts: 104	does it ever run on only one cylinder , when it splutters ... or does it always run on both ?