No Spark

[al_roethlisberger]

OK, well, unfortunately I don't have much for technical details at this point, but if this continues will get more specific info after next Tuesday.

 

 

But here's the deal.

 

The dealer rebuilt my engine for the case replacement, and now after reassembly no amount of fiddling will get it to spark, except if they artificially ground one of the leads out of one of the relays(this is where I need more detailed info). I believe they said this lead goes to the pin 19 on the ECU, but don't recall offhand.

 

I rode the bike in to the shop in December, and it ran fine then, so we all(myself and shop) agree that it has to be something they did, or have forgotten to reconnect.

 

Everything else on the bike powers up fine, lights work, fuel pump pressurizes, starter turns over.... e-v-e-r-y-t-h-i-n-g except no spark. Again, if they ground this lead, the bike will run though, but it shouldn't be directly grounded normally.

 

They've gone through the harness a few times, checked and rechecked every connection, swapped ECUs, checked all the relay sockets, swapped relays... you name it.

 

They have changed cam sensors with a new one, and have been on the phone with "Brad" at MGNA, who is supposedly their guru about these sorts of things.

 

I think the guys have even been in touch with Carl Allison, or at least pulled his schematics, on the issue.

 

 

So..... any thoughts off-hand? They are open to suggestions at this point. Electrical gremlins are always the worst, but this is really getting frustrating for everyone involved as they've been working on it for about 3 weeks now... this one problem. Other than this, the bike has been ready to go.

 

 

Thoughts ..... even crazy "out of the box" suggestions are welcome at this point.

 

 

What would keep the bike from sparking, that would have been related to pulling the engine?

 

 

Thanks

al

[jrt]

I can't see how pulling the engine would cause this, but I could see how messing up the wiring WHILE pulling the engine could.

 

Didn't you replace the coils (to dual-plug ones)? If so, do they hook up the same?

 

When the pin is grounded, is the resultant spark weak?

(I'm wondering if you have a ground loop)

 

Alternatively, is there an unintended ground? Does the battery drain?

 

Or, my last guess at the moment- the ground wire to the ECU might have come unconnected (desoldered/broke). This is just a variant on idea 2.

 

[al_roethlisberger]

I can't see how pulling the engine would cause this, but I could see how messing up the wiring WHILE pulling the engine could.

 

Didn't you replace the coils (to dual-plug ones)?  If so, do they hook up the same? 

 

When the pin is grounded, is the resultant spark weak?

(I'm wondering if you have a ground loop)

 

Alternatively, is there an unintended ground?  Does the battery drain?

 

Or, my last guess at the moment- the ground wire to the ECU might have come unconnected (desoldered/broke).  This is just a variant on idea 2.

 

50172[/snapback]

 

 

All good ideas

 

 

The coils are dual-output, but OEM, and hook into that harness with the stock connectors. The plugs do fire, and since coils are pretty simple things, we're pretty sure that they'd either work or not. They may look into hooking up some stock coils though just for grins and giggles.

 

 

We'll have to check if the spark is weak or not. I don't know. But the bike will run in the "shorted" mode. BTW, I also heard that grounding or exciting the lead will get the same result.

 

The battery does not drain.

 

We'll double check the ECU ground wire, but it looked fine, and I can confirm that it was hooked up.

 

 

Thanks

 

al

[Guest Nogbad]

If the lead to the relay that they are grounding is through a switched contact, try changing that relay.

[callison]

Have them check connector #57 V11 Sport wiring schematic and make sure it's connected.

[al_roethlisberger]

All the relays have been swapped from what I've been told.

 

Carl, thanks for the tip. Do you know which connector this is(physically on the bike, i.e. location)? It would help if I could just tell them which one to look for.

 

Thanks

al

[Paul Minnaert]

Al, you're having a problem for 3 weeks and just now tell us? :-(

Are yopu shure it is pin 19 on the ecu? because if you ground that, the a relay comes up that gives + 12v to the coils, a good thing, but also to the fuel pump and injection coils. And you tell us the pump runs?? If they connect their wire to the ground, you hear a relay click? The coils need 12v on one side, that can be checked easy. Also if that's not there.

IF it is pin 19 that doesn't contact to ground there is a reason for this, the ecu is missing a signal on an input, so it won't set the output free, or is defect.

[Cliff]

As Paul says pin 19 is an output from the ECU that is pulled low to energise the relay that powers fuel pump and coils and injectors.

 

If this were defective you wouldn't get any fuel pump unless the short was made directly to the relay.

 

If they've change ECU, it sounds like a harness issue. They should check continuity from pin 19 on the ECU plug to the relay.

 

Sad when dealers can't diagnose this stuff in a few days.

[Paul Minnaert]

Cliff, for the ecu to pull the pin 19 to ground, some conditions have to be tru, fi the +12v has to be > 1volts or something like that, is there a block diagram/schematic of the ecu where you can check what these conditions are?

[al_roethlisberger]

I'll have to verify the "pin 19" issue, as this is just from memory. I'll know more Tuesday when they are back in the shop and I can ask some more questions, and verify.

 

Thanks for all the thoughts so far.

 

al

[al_roethlisberger]

Al, you're having a problem for 3 weeks and just now tell us? :-(

 

50187[/snapback]

 

 

 

yeah... yeah....

 

 

Well, I've had a lot on my plate lately, and honestly, at this point... getting the bike back is really low on the priority list.

 

We are to move cross country(literally) in 3-4 months, and we've been going nuts selling stuff, fixing up the house, starting to pack, etc.... not to mention the new(ish) job ramping up.

 

 

Anyway, I really didn't 'engaged' with this problem until the dealer called me the other day asking about some of my wiring, and I went up there to point out what did what.

 

 

My opinion of the whole mess was that I rode it in without any problems, so they should be able to stick the engine back in, then I ride it off into the sunset. I'm a little upset that I'm going to have to potentially put in some of my time to get it working

 

They are good guys, and seem to be trying to rectify the problem, but I'm concerned about their ability to do so at this point.

 

 

Anyway, we'll see. I'll try to get more info Tuesday.

 

 

Carl, which connector is "57"?

 

 

al

[DeBenGuzzi]

I might be talking out my butt but did you take the wires off the battery and they not all get put back? I Almost did that when I charged it one of the grounds flung itself down under the battery tray and I almost missed it. Maybe I'm way off but something I could think of.

[DVH]

looking at the wiring diagram connector 19 is for the injection relay, which would ground the relay contactor coil. I would be inclined to think there is a earth from the ecu missing which looks like connector 23 and 24.

remove ecu relay, terminal 85 socket does it read to earth

connector 57 is a +ve for the ecu relay contactor coil,

also done the same as debenguzzi, left an earth off when refitting the batt

 

i would be inclined to copy the diagram and leave it with the dealer, it is a lot easier to follow than the guzzi diagram, I assume the dealer has somebody who can read a diagram?

[big J]

Wild stab in the dark,Al, is the flywheel pick up ok? Could it have been moved or damaged when removing/refitting the engine? Is the ecu reading crank rotation?

[jrt]

And importantly, does the person who correctly diagnoses the problem get a quiz point?