2017 Stelvio issue

[AH Fan]

Greetings all.
So recently an issue with throttling of my 2017 Stelvio NTX.
Machine has been running flawlessly since I purchased new and has now around 38000 klm and has now just recently started to develop a nasty snatchy rough run.
Seems to be burning lots of fuel as well as being extremely rough starting at around 3000 rpm up to 4000 rpm as the most noticeable area on the tack but there is definitely something wrong.
My Brother has the same machine and in a side by side roll on at 100 klph he just leaves me so its obvious somethings amiss.
TPS set/TB balanced and cleaned which everything appeared within spec.
Any ideas/....... any and all.
Mark (aka Beetle ) would be good if you could chime in please as I have been running your Stelvio map since new.

Thks in advance        Ciao

[guzzisteve]

To reach Beetle you have to go to   Griso.org or join the Griso Ghetto, he's not coming back here. He does read it from time to time.

Make sure your cables have no slack on Stelvio, all i can think of.

[PJPR01]

I would start by inspecting spark plugs and wires.

Then fuel filter…

Bad gas??

[lucian]

Did the issue start after tb balance / cleaning?  Has  either of the the sacred stop screws been tampered with?  Is the factory yellow paint on both stop screws and the link rod ends?  If these are intact i would recheck that the tps reset went through and you are at the required 4.8 ,  Next I would suspect a faulty plug cap , If you still have the oem caps they are prone to breaking and grounding to earth if not removed properly. I use a long flat screw driver inserted through the hole above the exhaust port ( thank you Pete Roper) and just pry the cap up from its base. SBO5E NGK is the replacement I used and I'm not 100 percent sure they are still available. But the miss fire from a bad cap can be intermittent and could be your problem .  Hope its something that simple.



,

[Tkelly]

Bad tps?

[AH Fan]

To reach Beetle you have to go to   Griso.org or join the Griso Ghetto, he's not coming back here. He does read it from time to time.

Make sure your cables have no slack on Stelvio, all i can think of.

Thx for that......... tried reaching him that way but no responce?
Cables appear to be fine

[AH Fan]

Did the issue start after tb balance / cleaning?  Has  either of the the sacred stop screws been tampered with?  Is the factory yellow paint on both stop screws and the link rod ends?  If these are intact i would recheck that the tps reset went through and you are at the required 4.8 ,  Next I would suspect a faulty plug cap , If you still have the oem caps they are prone to breaking and grounding to earth if not removed properly. I use a long flat screw driver inserted through the hole above the exhaust port ( thank you Pete Roper) and just pry the cap up from its base. SBO5E NGK is the replacement I used and I'm not 100 percent sure they are still available. But the miss fire from a bad cap can be intermittent and could be your problem .  Hope its something that simple.

Thx for all that.
No the problem came abruptly on the highway at speed......... never had that before.
I have a set of those plug caps in stock brand new standing by as well as a set of plugs just didn't want to start randomly plugging new parts into this issue when there may be an obvious issue with a component that I'm not capable of identifying at the moment.
Just for the record I would have thought a faulty coil/cap or plug would really show itself at higher loads and rpm obviously I could be wrong.
I guess I'm breaking out the new bits then............ was hoping to not approach this by process of elimination is all.

Thx again



,

[AH Fan]

Bad tps?

So a bad TPS would not show up on a Diag reset or dash code?

PS    All the throttle bodies are unmolested and all screw sealant is intact.

NOTE.   I wanted to get a hold of Mark (Beetle) to see if its possible that I may have a corrupt map due to some other anomaly.
NOTE  Or would a bad injector possibly cause this issue?

I had a similar issue with my 8V Norge many years ago but I'm not sure what the late Moto International (Micha) did but they sorted it out.

Ciao

[Tkelly]

Bad tps causes those symptoms.

[lucian]

You can observe the tps function with Guzzi diag by either watching the voltage values increase and decrease as you change throttle openings or use the graph function and watch for any non linear anomalies while slowly increasing and decreasing throttle openings

[AH Fan]

You can observe the tps function with Guzzi diag by either watching the voltage values increase and decrease as you change throttle openings or use the graph function and watch for any non linear anomalies while slowly increasing and decreasing throttle openings

Interesting........ .... thx for that.

[AH Fan]

Interesting............ thx for that.

OK all new NGK plug caps installed.......... still is running the same as it was before all that was done.
Next logical thing to check?
Or maybe I could get a list of what's left to check and or replace at this point?

Thx in advance

[AH Fan]

How about the possibility of a vacuum leak some where/
It still is equipped with the factory pollution control system complete with evap can.
Can I just pull the two blk lines off the throttle bodies and temporarily plug the openings on the throttle bodies and do a start test run?

[lucian]

i would definitely loose the evap canister and either plug the tb taps or some people connect them with a short piece of tubing which is fine.  I would also check the air filter to see if it may be oil soaked from running oil at the full mark on the dipstick . My 8v will expel oil to the airbox if I fill the oil much past half way between low and high marks on the dipstick. I wouldn't think a vacuum leak would cause more fuel consumption but would cause it to run lean. Did you pull the plugs ? if so how do they look?  Are they both the same color ect?

[AH Fan]

Checked the air filter and all that when I inspected the TB filter like new virtually no oil anywhere in the box or track to throtle bodies.I have had quite a few of these engines over the years and have the oil levels all sorted.
New plugs in and still runs stinky rich and shitty throttle up and hold.
Anybody else? We getting close as there's not much left is there?

Thx in advance

[AH Fan]

Oh and the old plugs looked uniform and a beautiful brown beige color...........put two ones in anyway with no change.

[AH Fan]

Going through this thread and noticed that I never reiterated to all of you folks the very beginning of what started this mess.
Coming back from a 3 day trip no rain very good weather. I pulled out to pass a few cars and accelerated hard to around 130 klm when out of no where engine did a full shut down with dash indicating something like ECU miscommunication with dash?? Never had that one before or since......... coasted to the side of the highway and turned the key off for a few seconds then turned it on and fired up the Goose.
From memory that was the beginning of the escalation of things leading to the present state. IN the back of my mind I thought that the old battery I had may have been the instigator some how hence I got a battery in there when I got home.
Hopefully that info may change things as far as identifying the issue/s

Regards.

[guzzisteve]

Maybe wind on the ECU ground wire, make sure eyelet crimp is good to wire. I had a customer with this issue on a Griso with disconnect on dash.

[lucian]

Again, I would plug in guzzi diag and check the tps value as well as watching the graph function to rule out a faulty tps sensor .  There should be some stored fault codes as well which may help lead to the culprit. Many of Beedles maps are open loop so the o2 sensor is flagged off, but if yours is closed loop it could be a bad 02 sensor which could cause overly rich running if sending bad info to the ecu. I am assuming you have the ability to plug in to the software since you mention doing a tps reset and loaded Marks map.