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Crank, no spark on V11s?


Guest KeS

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Ok, new problem with my '00 V11S.

 

Bike has been occasionally dying at idle since I've had it (six months). I've assumed the idle has just been set too low, occasionally it'll miss, usually on the left cylinder, and about half of those times it won't pick back up in time. No big deal, restarts immediately, I just haven't gotten around to adjusting the idle.

 

Riding around last weekend, bike dies at idle at a light. It didn't feel the same, instead of just a single miss that the bike didn't recover from, it just died immediately. Go to restart, strong crank, but the bike doesn't start within three seconds. Try several times, finally it starts and seems to run fine again for the rest of the day. Hmm.

 

I get home and park the bike, next day when I go to ride it, strong crank but won't start normally. After several five-second attempts battery starts to weaken, I put it on the charger and leave it. Next day it is fully charged, I try to start again, it still takes much longer than usual, but finally starts and idles ok for a couple of minutes, then dies and again won't restart (still cranking strongly). Put it back on the charger and get on with my life.

 

Fast forward to this weekend, when I have a chance to do a little troubleshooting. Here's what I've done so far, and the results:

 

- Try to start bike, strong crank but no fire (usually starts in two seconds when cold).

- Pull all fuses and relays and replace (this bike does have updated relays). No change.

- Open gas cap in case I have a fuel-vacuum issue. No change.

- Pull plugs. They look ok if a bit rich. Fuel smell but not wet. Holding one on the cylinder head, crank the bike, no spark. No change other than that the bike cranks a lot faster with no plugs in it. :)

- Bypass Power Commander unit. No change.

- Headlights, neutral light, indicators, all the other electrics appear normal throughout all this once I got the battery recharged from the initial extended cranking sessions.

 

So... it seems like ignition? Except that the "hard start but runs fine after" symptom sounds more like fuel? All this hard/no starting is definitely new, and while the bike has always died at idle when cold occasionally, it has never died at speed or any other way that suggested an ignition problem.

 

I'm a terrible diagnostician - I can bolt and unbolt stuff ok, but that's about it. Am I describing a known issue like a flaky coil that I can replace with high confidence, or can someone suggest a good series of diagnostic steps, or do I need to bite the bullet and arrange a tow to the shop?

 

Thanks for any suggestions!

 

KeS

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Will do - but that would stop it from throwing spark? Another bit of info is that the bike hasn't had any work done recently that would account for this - haven't been groveling around in the harness at all.

 

KeS

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Guest Nigelstephens

If you have no spark then I would suggest you check the connectors to the coils, the HT leads to the plugs and the connector to the ECU. You dont have to have disturbed it recently as oxidation to the connectors can happen over time and lead to trouble.

 

Try seperating them and checking the condition of connectors. If there is any corrosion then this could be the cause. Just clean with wire wool and use a little silicon grease or petroleum jelly to prevent further corrosion.

 

It could be plug caps too. but unlikely for both to be affected together. Are both sparks definately not working when you crank?

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Guest ratchethack

Will do - but that would stop it from throwing spark? Another bit of info is that the bike hasn't had any work done recently that would account for this - haven't been groveling around in the harness at all.

 

KeS

KeS, if y'er anywhere close to our infamous San Diego Coastal Marine Layer, you may well be familiar (or not?) that y'er Guzzi ain't gonna be happy very long without some extra care & attention to her electrical connections, as Nige pointed out. The Brits, most raised by Lucas, the Prince o' Darkness Hisself <_< , know a thing or 2 about dodgy electrics and the tortured migration habits of electrons through corrosion-induced points of high resistance!!

 

If you haven't been "groveling around in the harness", it might be time. . . . ;)

 

I'm a little fuzzy on this because it's probably been a few years, but I recall reading somewhere about potential ground path/connector problems between the regulator and coils, as Nige mentioned above. It was compelling enough at the time to make me do some preventive maintenance and trace the leads, cycle the connectors, apply dialectric grease, re-crimp where needed, brighten up the frame mounts for the coils, and re-fasten the coil mounts with threadlocker -- which the Luigi's in Mandello seem to've held very dear, and applied only in some o' the most unexpected places. :unsure:

 

Good luck. :luigi:

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start with the leads from coil to plug. In the wet of the PNW, this is a common trouble area if you ride at all in the rain. Had a 4-cyl that would become a twin at the most inappropriate moments due to this, and a tripple that was stumbling and running roughly- looked down one night as it was missing and it looked like a thunderstorm between two of the leads and the head.

 

They can corrode inside the cap, so it looks fine but won't pass a spark.

 

Good Luck,

 

Garsdad

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Assuming you are not getting spark at either plug, I would look for a common problem, like the ECU or a wire feeding power to both coils.

I don't think the coils are grounded except through the ECU, and the spark plug gap.

If you hear the fuel pump than the line to the coils should be getting power, but check at the coils.

Are the injectors flooding the engine? This would be a clue as they share the same power line and also depend on the ECU and the engine position sensor.

Check out

http://www.thisoldtractor.com/guzzi007/sch...9_V11_sport.gif

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Long a fan of connector maintenence and dielectric grease for the Guzzi, I recall Gary Cheek's good advice, "Use copper anti-seize paste." It displaces moisture and increases conductivity. :thumbsup:

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Assuming you are not getting spark at either plug, I would look for a common problem, like the ECU or a wire feeding power to both coils.

I don't think the coils are grounded except through the ECU, and the spark plug gap.

If you hear the fuel pump than the line to the coils should be getting power, but check at the coils.

Are the injectors flooding the engine? This would be a clue as they share the same power line and also depend on the ECU and the engine position sensor.

Check out

http://www.thisoldtractor.com/guzzi007/sch...9_V11_sport.gif

 

Yes, that seems more likely. Followups:

 

Grounding the plug base to the cylinder head should be adequate, right? That's where it grounds normally.

 

Will check for fuel pump noise, I'm not usually attuned to it.

 

The engine isn't flooding - in fact when I pulled the plugs they weren't wet, though they did smell of fuel. Is that an indication I have intermittent injectors along with spark, and would that point to a common cause?

 

Is the engine position sensor the same thing as the cam angle sensor I see blamed for similar kinds of intermittent-to-increasing problems? Is there a test for the thing?

 

If I'm cranking, I'm past all the clutch/neutral/etc. interlock switch problems, right?

 

Is it that unrealistic to expect the Guzzi to work as reliably as the K12RS and Gixxer that are parked in the same garage and ridden just as frequently (2-3 times/week)? Ok, never mind that one, I know the answer by now.

 

It's a little frustrating in that the original owner had this thing beautifully maintained - for example the infamous bullet connectors for the clutch switch were changed to spade connectors and shrink-wrapped, all relays done, the PCIII neatly mounted along with a pigtail for battery charging. Just a lot of attention to detail, and I still can't trust the bike to start and run for any length of time. I could have a Buell with this level of reliability, and at least have a dealer to go to.

 

(sigh) Thanks for the pointers.

 

KeS

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Updated diag info:

 

No spark either cylinder.

No fuel pump sound.

When ignition or kill switch cycled, I hear a couple of the relays click, and the Power Commander does its power-on check - that's all I see/hear. (Indicator lights/headlight etc. are all still normal)

CPU appears to be grounded by an external wire to one of the screw cases, disappearing into the harness - that looks normal and is tight/clean.

 

KeS

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Guest Nigelstephens

You should hear the fuel pump run for a couple of seconds when turning on. The fuel pump is powered via the ECU and this via the relay that you can probably hear clicking.

I would check the relays. Remove each and check contacts then reinsert.

 

Cant remember where the fuses come in the circuit but if you have a meter you could check for 13v between the fuse (both sides) and the frame(-ve) when turned on and kill switch on run.

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Yes, that seems more likely. Followups:

 

Grounding the plug base to the cylinder head should be adequate, right? That's where it grounds normally.

Yep, you kinda need three hands to do it.

Two to start and one to hold the plug (not a light bulb joke)

I have heard that cranking when plug is not grounded is a bad idea.

 

The engine isn't flooding - in fact when I pulled the plugs they weren't wet, though they did smell of fuel. Is that an indication I have intermittent injectors along with spark, and would that point to a common cause?

Whatever is killing the spark is probably killing the fuel injectors and or the fuel pump.

The fact that you don't hear the fuel pump confirms the problem.

Relays are the most likely culprit.

I have never heard of a GEI relay fail, but if that is what you have, it could be a first.

 

 

Is the engine position sensor the same thing as the cam angle sensor I see blamed for similar kinds of intermittent-to-increasing problems? Is there a test for the thing?

Yah, but I don't know how to test it.

No problem though. No fuel pump sound is the key clue, and the sensor is not likely the probllem.

 

If I'm cranking, I'm past all the clutch/neutral/etc. interlock switch problems, right?

Most likely. But stranger things have happened.

 

It's a little frustrating in that the original owner had this thing beautifully maintained - for example the infamous bullet connectors for the clutch switch were changed to spade connectors and shrink-wrapped, all relays done, the PCIII neatly mounted along with a pigtail for battery charging. Just a lot of attention to detail, and I still can't trust the bike to start and run for any length of time. I could have a Buell with this level of reliability, and at least have a dealer to go to.

 

(sigh) Thanks for the pointers.

 

KeS

You are in San Diego! We have two excellent Guzzi shops :grin:

If you had a bad experience, you might give them a second chance.

Or continue on track with your do it yourself repair. I think you are close to a solution.

NigelStephens advice is good. The relays in question are the two rear most. The rear most (injection relay) being the most likely.

If you get desperate, I'll work for microbrew beer.

Ratchethack will work for fine Scotch and Cigars.

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Yep, you kinda need three hands to do it.

Two to start and one to hold the plug (not a light bulb joke)

I have heard that cranking when plug is not grounded is a bad idea.

Whatever is killing the spark is probably killing the fuel injectors and or the fuel pump.

The fact that you don't hear the fuel pump confirms the problem.

Relays are the most likely culprit.

I have never heard of a GEI relay fail, but if that is what you have, it could be a first.

Yah, but I don't know how to test it.

No problem though. No fuel pump sound is the key clue, and the sensor is not likely the probllem.

Most likely. But stranger things have happened.

You are in San Diego! We have two excellent Guzzi shops :grin:

If you had a bad experience, you might give them a second chance.

Or continue on track with your do it yourself repair. I think you are close to a solution.

NigelStephens advice is good. The relays in question are the two rear most. The rear most (injection relay) being the most likely.

If you get desperate, I'll work for microbrew beer.

Ratchethack will work for fine Scotch and Cigars.

 

I'll swap relays around, but I definitely hear two, and no fuel pump. (My gixxer goes through this bizarre self-test with the tach needle and fuel pump charge whenever you put the sidestand up!)

 

I've grounded the plugs properly with a clamp as a third hand, and I definitely get no spark either side.

 

Who's the other shop? GP is the one I'd know to go to. It's not that I've had a bad experience, I have none at all - bike hasn't needed service since I got it, and the other bikes go to dealer shops.

 

KeS

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KeS

 

This sounds to me like an intermittend power supply to the ECU.

You don't hear the fuel pump, the spark is absent, the injectors do not work. All these acuations occur from the ECU.

Check the voltage from the fuses to the relays and further into the ECU. The relays might be actuated, but does the current arrive at the relay to be connected to the ECU?

There is a diode switched between the ECU relay and the ECU. If this fails or unsolders, the ECU is inactive. Check this too. You get access to this if you unscrew the relay sockets. It is switched into the harness at the connection to the relay.

Try to get a plan of the electrical circuit, the one in the owners manual is useful if you make an enlarged copy. The only thing you need is a checking light and some patience.

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KeS

 

This sounds to me like an intermittend power supply to the ECU.

You don't hear the fuel pump, the spark is absent, the injectors do not work. All these acuations occur from the ECU.

Check the voltage from the fuses to the relays and further into the ECU. The relays might be actuated, but does the current arrive at the relay to be connected to the ECU?

There is a diode switched between the ECU relay and the ECU. If this fails or unsolders, the ECU is inactive. Check this too. You get access to this if you unscrew the relay sockets. It is switched into the harness at the connection to the relay.

Try to get a plan of the electrical circuit, the one in the owners manual is useful if you make an enlarged copy. The only thing you need is a checking light and some patience.

 

Well, some ability would be helpful, too. My understanding of electical current is about at the "lights good, shock bad" level. And some would argue that for me, the shocks are actually therapeutic. :)

 

Thanks, though, it does seem that we're narrowing down focus towards ECU-related items.

 

KeS

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