2017 Stelvio running issues

[Twin AH]

Having a few issues with my 2017 Stelvio NTX as of late that may require Mark ( aka Beetle )

Where are you Mark.

Regards.

[pete roper]

I don’t think Mark posts here. What’s it doing?

[Twin AH]

Hey Pete thx for chiming in......... tried to get ahold of Mark with no avail.

I have a bit of response from others over on Wild Goose Chase.

At this point its starting ok but when you try and hold a steady rpm from 2k all the way through to about 5K it surges and wanders all over the place.... cant hold steady throttle when at load(moving) either??

Burning fuel like a bugger and smells the part?and is not making much power as I found out having a 100kph roll on with my Brothers stock same year Stelvio... he left me for dead??

Was hoping someone might have had something like happen abruptly to their lump in the past.......... also hoping NOT to randomly starting plowing new parts in it at random in hopes of getting lucky.

PS          None of the dealers or shops that I have spoke over the years know anything about these machines unfortunately........... for me.

[pete roper]

Ah, found the info on WG.

First thing to check, as suggested, would be the plug caps. Get it in a darkened garage and take the plug lead covers off. Start the bike and look and listen for the spark *Snapping* to earth at the rocker cover. Even if you can’t see it you should be able to hear it.

When you last serviced it, how did you remove the plug caps? If yo pried, pulled or levered them from above you will almost certainly of damaged them. They tend to tear at the right angle where the cap turns to meet the lead. Once that has happened it doesn’t take long for the spark to start earthing out. It may not happen immediately though so don’t be surprised if it started mid ride.

The way to remove the caps on the 1200-8V’s is to get a long, thin, flat bladed screwdriver and insert it through the cooling tunnel in the head just above the exhaust manifold. Poke around and you’ll feel the rubber of the cap. Hook the tip of the screwdriver under the bottom of the cap and lever it up, off the plug. Once it has unclipped from the top of the plug, then, and only then, do you pull it up from above.

The excessive fuel use and unburnt fuel smell will be from the uncombusted fuel passing through the non-firing cylinder. If you are running the original pipe, or an aftermarket one with a catalytic converter, the cat may well of been damaged by the unburnt fuel combusting in the cat. Look for discolouration at the front of the exhaust can.

It is very unlikely it is an ecu or mapping problem. The W5AM is pretty much unbreakable and the files can’t corrupt themselves. It will have a physical cause and plug caps are the most likely one.

Edited 7 hours ago by pete roper

[activpop]

Pulling the plugs and looking at them might give a hint as to what cylinder is misfiring.

[Twin AH]

3 hours ago, pete roper said:

Ah, found the info on WG.

First thing to check, as suggested, would be the plug caps. Get it in a darkened garage and take the plug lead covers off. Start the bike and look and listen for the spark *Snapping* to earth at the rocker cover. Even if you can’t see it you should be able to hear it.

When you last serviced it, how did you remove the plug caps? If yo pried, pulled or levered them from above you will almost certainly of damaged them. They tend to tear at the right angle where the cap turns to meet the lead. Once that has happened it doesn’t take long for the spark to start earthing out. It may not happen immediately though so don’t be surprised if it started mid ride.

The way to remove the caps on the 1200-8V’s is to get a long, thin, flat bladed screwdriver and insert it through the cooling tunnel in the head just above the exhaust manifold. Poke around and you’ll feel the rubber of the cap. Hook the tip of the screwdriver under the bottom of the cap and lever it up, off the plug. Once it has unclipped from the top of the plug, then, and only then, do you pull it up from above.

The excessive fuel use and unburnt fuel smell will be from the uncombusted fuel passing through the non-firing cylinder. If you are running the original pipe, or an aftermarket one with a catalytic converter, the cat may well of been damaged by the unburnt fuel combusting in the cat. Look for discolouration at the front of the exhaust can.

It is very unlikely it is an ecu or mapping problem. The W5AM is pretty much unbreakable and the files can’t corrupt themselves. It will have a physical cause and plug caps are the most likely one.

OK then............ tomorrow I will tear into it and replace plug caps with new as well as plugs.

Others have stated its probably a failed TPS.

Your thoughts on that?

[Twin AH]

3 hours ago, pete roper said:

Ah, found the info on WG.

First thing to check, as suggested, would be the plug caps. Get it in a darkened garage and take the plug lead covers off. Start the bike and look and listen for the spark *Snapping* to earth at the rocker cover. Even if you can’t see it you should be able to hear it.

When you last serviced it, how did you remove the plug caps? If yo pried, pulled or levered them from above you will almost certainly of damaged them. They tend to tear at the right angle where the cap turns to meet the lead. Once that has happened it doesn’t take long for the spark to start earthing out. It may not happen immediately though so don’t be surprised if it started mid ride.

The way to remove the caps on the 1200-8V’s is to get a long, thin, flat bladed screwdriver and insert it through the cooling tunnel in the head just above the exhaust manifold. Poke around and you’ll feel the rubber of the cap. Hook the tip of the screwdriver under the bottom of the cap and lever it up, off the plug. Once it has unclipped from the top of the plug, then, and only then, do you pull it up from above.

The excessive fuel use and unburnt fuel smell will be from the uncombusted fuel passing through the non-firing cylinder. If you are running the original pipe, or an aftermarket one with a catalytic converter, the cat may well of been damaged by the unburnt fuel combusting in the cat. Look for discolouration at the front of the exhaust can.

It is very unlikely it is an ecu or mapping problem. The W5AM is pretty much unbreakable and the files can’t corrupt themselves. It will have a physical cause and plug caps are the most likely one.

 

7 minutes ago, Twin AH said:

OK then............ tomorrow I will tear into it and replace plug caps with new as well as plugs.

Others have stated its probably a failed TPS.

Your thoughts on that?Also machine has always had a Mistral can no cat but still has evap system from factory.

 

[pete roper]

I’d be very surprised if it was the TPS. I’ve only ever replaced one and that Thad been submerged at some point!

You can check it fairly easily using Guzzidiag. Just look at the value as you open and close the throttle. Any sudden jumps or drops will be immediately obvious.

[Twin AH]

Thx to all for commenting.

 

Ciao for now