At my wits ends: 2013 Stelvio Not Starting

[Kuni0]

Hey everyone. As the title implies, I'm at my wits ends and utterly confused. There's a good amount of people here with wonderful knowledge, so I thought I would see what you had to say. (I am aware, there's that massive Stelvio megathread on ADVrider, and other good and questionable forums to look for info, but 'AI, powered by Google' has made searching anything technically descriptive and relevant impossible)

About a month ago, I was on my way back home on my Stelvio when suddenly it felt like it was running on 1 cylinder. I would give it full throttle and it barely made a difference to go forward and if I let off the throttle, it would die. I got it towed back deciding it best to not chance it riding on the highway, and have barely gotten it to start. Putting the GuzziDiag on, I got several codes (P0130, P0136, P0335, P0352). Having had a cam position sensor fail and leave me stranded about 3 years ago, I had a spare one and swapped that in hoping for a fix...

which didn't work. A previous forum I found (For V7) said the sensor should be around 650 ohm resistance to work. Out of curiosity, I test the old and new sensor. Both 650 ohm. The new sensor didn't work. And that leads into the next series of steps that I took...

A friend said spray some carb cleaner down the intake to help prime it. Didn't work

Check the plugs since didn't actually check them. Both are sparking

Check all the fuses to see if any are blown or corroded. All check out

I thought maybe the fuel pump wasn't pumping fuel or the fuel filter got clogged (it did rain here at the time the bike broke down, and the bike has never had the filter replaced in the 60,000 miles I've owned it). I pulled the injectors and they're squirting (I tired to pull the fuel pump, but couldn't get off the retaining ring and cause a fuel leak, but that's a separate issue). 

Spray a liberal dose of carb cleaner directly in the intake (no air filter) and am able to get it to start and idle (horribly) but as soon as I give throttle, it dies

Check the valve clearances fearing the worst. Measure 0.10 mm intake 0.15 mm exhaust on both... perfect...

Different friends suggest that although the plugs are squirting, they may be clogged from water or contaminants. Buy an injector cleaner kit, clean the injectors and still no start (Still have spark and fuel)

Do some digging in the forums and find cased where the chain guide snapped and caused timing to go off and other such terrible destructive events that describe my situation. Take off oil splasher from both cams and find them perfectly aligned (looking at the guides and chain itself with a flashlight from the bottom down, I saw no damage)

Think that maybe the battery is bad and change it for one from my working bikes (2016 Yamaha FJ-09). No start

Re-read with Guzi-Diag and just see P0335 code

Finally found a video seemed to go into detail about diagnosing cam position sensor issues (Link to the video found here). Even though it's for cars, thought I'd give it a try. Disconnect the cam sensor to the wiring loom and get these results: Ground: 12.4V, White: 1.5V, Red: 2.5V (video says white and red (Low and High signal) should be ~5V and anything lower is a problem). Think I find the problem, and realize it's in the worst place possible (either in the ECU or wiring loom). Try again turning over the engine while checking high and low signal and still 2.5 and 1.5V

Start to dig into the wiring harness, but stop. Ask some friends and they suggest different things (Look at the voltage in an oscilloscope to see a good sinewave, check all the grounds for low voltage) and that pretty much brings me here. 

Short of buying an oscilloscope to test the sine wave of the current, I don't know what I can do to help troubleshoot this bike. 

Before I proceed there, is there 

1. A way to check the connections from the camshaft position sensor wiring --> ECU connection? I've done a primative continuity test with Ohms and have seem about 0.1-0.01 Ohm from all 3 connectors. 

2. Check the ECU. When I check high and low signal from the batter to the ECU, I see 10V for both instead of the aforementioned 2.5 and 1.5 V. Is this significant and direct it down to my wiring harness? 

3. I check the ground connections I can find. There's the ECU ground that I looked good (cleaned and re-attached) and the two grounds near the starter motor (again, cleaned and re-connected) and still not start. Is there a 4th ground that I should check as well? 

 

Anyway, that's all I can think of at the moment. I'll try to answer any questions related to troubleshooting as soon as I can. And thank you in advanced. 

Edited Tuesday at 02:57 PM by Kuni0

[pete roper]

Sorry, I missed this. I have a couple of ideas. I’ll cover them in a bit when I’m not on my phone. 

[pete roper]

Who has been servicing it?

How were the plug caps removed?

[gstallons]

Pete , are these solid core wires and the plug caps screw in ? Also , if these are solid core wires , they will have resistors in the caps ?

My red frame had a hick-up / miss and one of the caps were "open" .

[Kuni0]

Well, I'm the ape that been servicing my Stelvio, and have for the past 60k miles. 

Whenever I'm removing the plug caps, I take a long allen head socket and guide it under the plug cap and pop it up, as seen in the picture below. (feel free to call me a moron if I've actually been screwing it up)

Edited Tuesday at 05:36 PM by Kuni0

[Kuni0]

Also, running plug caps. These are the standard ones from the factory to my knowledge

[gstallons]

What I am referring to (as in the V11) are the caps / boots that screw on to the ends of the spark plug wires . and push on to the spark plugs.

[pete roper]

Well, that is likely your problem. The caps are very soft and tear easily. Levering them off from the top as shown almost invariably damages them. It may not be obvious at first glance but if you remove the lead covers and spin the bike over in a dark garage you will likely hear, and probably see, the spark *Snapping* to earth between the right angle of the cap and the rocker cover.

The factory supplied, at enormous cost, a sort of grabby tool that you could slide down the cap to grip it and pull it up. I’ve never seen one! Ain’t nobody gunna pay for that nonsense!

The way to remove the caps without damage is to get a long, thin, flat bladed screwdriver and poke it into the cooling tunnel in the head just above the exhaust manifold. Prod around with it and you’ll feel the soft rubber of the cap. You can then hook the end of the blade under the bottom of the cap and lever the cap up, off the electrode. Once the cap’s clip is clear of the electrode tip then and only then do you grab the cap at the top and wriggle it out with a gentle twisting motion. When reinstalling give a light smear of rubber grease around the sealing ‘rings’ on the cap to make it easier to slip out next time.

Now the common replacement for the rather delicate original caps used to be NGK SB05-E or F caps, the suffix letter denoting the fitment for the tip shape of the plug centre electrode. Thing is NGK have ceased production of plug caps due to lack of demand, (Everything having moved to plug top coils.) but nature abhors a vacuum and there is another mob whose name I can’t remember off the top of my head who have stepped into the breach. I think though I put a link to their site up on Griso Ghetto, (Which is probably your best source for 8V info and yes, we like ALL CARC bikes so you won’t be ostracised!). The NGK caps don’t have the right angle tops and you have to bend the HT lead over to fit it under the lead cover which looks a bit ugly but it works. If you’re lucky you may find a set of NOS NGK caps on fleabay or the like.

Next up in your steep learning curve will be understanding how the W5AM ECU controls the engine and why you should never move the ‘Sacred’ throttle stop screw while tuning it!

Edited Tuesday at 08:03 PM by pete roper

[Pressureangle]

https://firepowerparts.com/spark-plug-cap-sb05e-replaces-ngk-8374/

 

Here's another one that may be a better fit- of course, I have no 8v nor this plug boot to hand, but if it was me I'd waste the money on a set to try. 

https://firepowerparts.com/spark-plug-cap-xb05f-replaces-ngk-8062/

 

Edited Tuesday at 08:55 PM by Pressureangle

[pete roper]

Worth a try but I don’t think it will be long enough.

[pete roper]

11 hours ago, gstallons said:

Pete , are these solid core wires and the plug caps screw in ? Also , if these are solid core wires , they will have resistors in the caps ?

My red frame had a hick-up / miss and one of the caps were "open" .

They are copper core wires and yes, resistor caps. The resistor can be damaged by careless prying but in this case I’m pretty certain the problem is down to the rubber of the cap being torn. The fact it was raining when the problem arose is one indicator.

Thing is when damaged the caps quite often don’t start arcing immediately. It seems to usually take about five to thirty Km for the problem to appear. Just far enough for it to be bloody inconvenient! Once the arcing happens though it’ll form a carbon track through the crack in the rubber and it’s all over red rover!

Taking the plugs out and putting them in the caps and testing them against the heads is fine. You’ll still get a spark at the plug because the crack in the cap is away from the head and the spark isn’t being stressed. Electricity takes the path of least resistance and outside of the engine jumping the plug gap is easy. Once the plug is in the head the conditions, heat, compression etc. are far more hostile and so the spark looks for an easier route to earth. A nice damp crack in the boot of the plug cap is perfect! Wham-Bam-Thankyou-Mam and it’s all over bar the shouting.

It’s really important NOT to ride in this condition as the uncombusted fuel from the dead cylinder gets pumped through into the exhaust where it can combust in the catalytic converter. That as you can guess is when the fun really starts!

[gstallons]

I use a silicone dielectric grease to put in the hole of the boot (about as much as you would put toothpaste on a toothbrush) in the bore of the cap and a smear around where the boot contacts the bore of the cylinder head .  I use Motorcraft because it is readily available here . They are all similar so no one brand is better than the other. 

Edited Tuesday at 11:44 PM by gstallons
spelling error

[pete roper]

Caps.

 

http://kandstech.com/productreleases/sprc.pdf

 

Note. This will be useful for V11 owners too as you will probably need new caps after you bin it. From memory the NGK’s were SB05’s caps.

Edited Wednesday at 12:16 AM by pete roper

[docc]

12 minutes ago, pete roper said:

Caps.

 

http://kandstech.com/productreleases/sprc.pdf

 

Note. This will be useful for V11 owners too as you will probably need new caps after you bin it. From memory the NGK’s were SB05’s caps.

Plus, early V11 Sports used the red Champion caps.

[gstallons]

I have some NOS (old) Champion and NGK caps I inherited from a friend and have them laying around here. You can get them from any good bike shop .