2020 V85TT CEL after/during heavy rain

[Grabcon]

I have a 2020 V85TT with 33k miles, I bought the bike with 3200 miles on the clock, owner two years now. The bike runs great most of the time, 99%. But in the last 17k miles or so I have had an issue during heavy rain and after. I live in SE Arizona so I don’t get a lot of rain and if I do I won’t ride unless I am already out and about. So this issue only happens on trips.

The problem is that I will get a CEL while riding, sometimes the bike will have a significant misfire and always in an uphill direction. Sometimes the bike has sat in the rain because we were traveling and it may have been parked for the evening, then when we start out the next day I might get the CEL after some miles, don’t know how many it is random. Sometimes the CEL will go out on its own other times I will need to check and clear codes. Codes always show as an O2 sensor.  Early on I pulled the sensors and tested and they test fine. After a tank of gas or so the intermittent misfire will stop.

My original thought is that it might be an electrical connection issue, I have pulled the tank and got thru all connections cleaning and reseating. It still happens. This last weekend I went on a 1300 mile trip and hit heavy rain 10 miles from destination so 650 miles in the trip. The CEL lite up but no misfire. The bike sat for three days and we had heavy rain on and off for those days. We packed up and left started the bike and no CEL and sunshine. Filled up and went 30 or 40 miles and the CEL came on along with the misfire. Again random misfire always uphill. This went on for 200 miles. CEL on the whole way, did another fill, misfire lessened but still there. CEL didn’t go out. Got to the motel for the night and disconnected the battery overnight. As a note when the misfire happens the onboard computer AVG Miles MPG drops into the teens From whatever it  was reading. Misfire stops MPG goes back up.

Reconnected the battery in the morning, did a fill rode 335 miles with a second fill midway. No issues.

So the questions is “Am I getting water in the tank when it rains?” IF so how, “is the cap leaking?” I am at a loss as to what cause the issue.

Any constructive thoughts would be good.

[guzzisteve]

Plug the bike in when light is on to find out what goes on. Plug into software to tell you. It's the way it's made, or look at info on dash for codes.

[Dirk_S]

Can you unplug the Lambda sensors temporarily to see if the code pops up again?

[rocker59]

1) I would be concerned about water contaminating the fuel.  Next time you park it out overnight in the rain, cover the bike.  Bike covers are not expensive.  I always carry one when on long trips.  Keeps prying eyes away from the bike, and keeps the bike dry in the event of overnight monsoon rains.

2) make sure your plug wires are good, and are not being fouled by the heavy rain.

[kingoffleece]

+1.  I always bring a half cover with me on trips.
If you need a dealer Matt at ManicMoto in Queen Creek is very good.

[Grabcon]

Plug the bike in when light is on to find out what goes on. Plug into software to tell you. It's the way it's made, or look at info on dash for codes.

The only code ever shown has been an O2 sensor code. If the senors are good than all the code tell you is that it is fueling issue.

[Grabcon]

Kind of tough to cover the bike while riding in a heavy rain. Plus by then it is too late.

[rocker59]

Kind of tough to cover the bike while riding in a heavy rain. Plus by then it is too late.

"Sometimes the bike has sat in the rain because we were traveling and it may have been parked for the evening, then when we start out the next day I might get the CEL after some miles"

This scenario is repeatable and you can inject the waterproof cover into the mix to help rule in, or rule out water intrusion into the fuel after sitting in the rain.  That's why I suggested the idea.

Personally, I think you have a very high probability of fuel contamination. 

The drain on the fuel filler well may be blocked and water is getting past a fuel cap seal.  I've had to clean the drains out in years past.

You asked for help, and I'm just offering some suggestions learned from past experiences over the past 30-years.  It rains a whole lot more in the Ozarks than it does in Arizona, so I've faced a few trials over the years.

 

[Tkelly]

In your first post you say the bike has no issues now,I don’t get what you are asking.I had an idiot light on my Stelvio supposedly caused by a hard to reach bad connection under the fairing come on during strip out west in 2016.At some point it went out and never came on again.I guess it fixed itself,maybe yours did too.

[Grabcon]

"Sometimes the bike has sat in the rain because we were traveling and it may have been parked for the evening, then when we start out the next day I might get the CEL after some miles"

This scenario is repeatable and you can inject the waterproof cover into the mix to help rule in, or rule out water intrusion into the fuel after sitting in the rain.  That's why I suggested the idea.

Personally, I think you have a very high probability of fuel contamination. 

The drain on the fuel filler well may be blocked and water is getting past a fuel cap seal.  I've had to clean the drains out in years past.

You asked for help, and I'm just offering some suggestions learned from past experiences over the past 30-years.  It rains a whole lot more in the Ozarks than it does in Arizona, so I've faced a few trials over the years.

Thanks for the input this is what I was thinking as well. Unfortunately the fuel filter is internal and attached to the fuel pump. I saw a write up on how to replace the fuel filter on GTM. Not difficult just a PIA to do.

[Vagrant]

I doubt it's fuel.
The 20-23 models have a big gap under the switch gear on the right side that controls the aux. driving and head lights. Look for the gap, I think it shows with the switch forward but it could be in the back. I don't remember. Flush it out with Deoxit. Then clean the plastic and slide i piece of electrical tape under the switch to cover the hole.
The V7's have had O2 sensor issues from water / washing, etc. but I don't remember any with the v85. Being as it's a 2020 just spend $100 and get a Beetle map and that will kill the O2 sensors and eliminate at least that item. Also on the v85 that light can mean just about anything.

[Grabcon]

I doubt it's fuel.
The 20-23 models have a big gap under the switch gear on the right side that controls the aux. driving and head lights. Look for the gap, I think it shows with the switch forward but it could be in the back. I don't remember. Flush it out with Deoxit. Then clean the plastic and slide i piece of electrical tape under the switch to cover the hole.

 Also on the v85 that light can mean just about anything.

I will look at the switch gear. Thanks

I use at the ODBLink LX bluetooth and android app to read and clear the codes. It always show O2 sensor. I brought it to the dealer early on around 15K miles and all they saw was an O2 code.

I will look at Beetle Map

[vf84pc]

Rain and misfire scream electrical problem. When the bike starts misfiring spray WD-40 ( an old BSA trick) on the ignition wires and coils. If the misfiring stops you need new wires or coils. Since rain is not common in AZ will it start misfiring if you spray it with a hose? Since it is a 2020 I would wager a case of beer if you replace the wires your problem will be solved.

[John A]

Reminds me of my new Cal2 when I lived in Shreveport. There was a railroad underpass that would have about six inches of water after heavy rain on my way to the base. It would short out the kickstand kill switch and kill the engine so I had to put my feet down in the water . Then off to roll call at the base. After the second time that switch was in the trash.

[Bulldog9]

This (or similar) happened to Bill Hagan on the way to the Guzzis in the Blue Ridge rally this summer. We rode through Forest Gump Rain for 3-4 hours. At one point when we stopped on the side of the road to get oriented and find our way in to the campground, the ECU Error prevented him from restarting the bike. We did the 'remove the leads from the battery, touching them together and turning on the key and hitting start to pull all voltage out of the system. This got him restarted and to the campground, though the CEL and error messages returned. Once there we 'cleared' things again, loosened the switchgear,  sprayed some deoxit in the switch gear, and restarted. He hasn't had a problem since.

I don't have a V85, but there are a ton of switches, cruise, ride modes, etc. I have no idea which switch got moisture in it, but I would imagine some preventative spray of deoxit in these switches at the start of the riding season may be a good idea.

His case was not water in the fuel, or getting sucked in the airbox when riding in the wet weather, but water in the switch gear. This was on a 2022/23 model, the Black/White Police edition.

[MikeP996]

FWIW, my first Ducati, a '92 900SS was never electrically right after a 4 hour ride in heavy rain from Centerport (Long Island), NY to Lake Placid.  I owned it for another year but random electrical strangeness occurred constantly and none of my cleaning of contacts, etc helped.  Don't know if it's an "Italian" thing or not though I rode my V7 100 miles in the rain from the sellers house to mine when I bought it with no apparent issues.  Admittedly, it was a shorter ride and the rain wasn't as heavy.

[Grabcon]

Okay I don't want to re hash old stuff so go to the first post on this thread. It has been a year and the Cel has returned this June the wife and I were gone for the month and had a lot of rain and the CEL returned many times with a mid-fire. The OBD2 code reader I have (a cheap one) always returns a P0154 which according to my Google search came back with results I don't remember from a year ago.

Error code P0154 means Oxygen Sensor Circuit No Activity Detected (Bank 2, Sensor 1), which indicates that your upstream oxygen sensor has stopped sending a proper voltage signal to the engine computer.

If this code only happens when it is raining, water is likely getting into an electrical connection or causing a short circuit.

Why Rain Triggers P0154
Water in the Connector: Rainwater can seep into the plug for the oxygen sensor. This moisture shorts the signal wires or blocks the low-voltage electrical current.

Damaged Wiring Insulation: A crack in the wire casing lets water touch the bare copper wire during a downpour. This disrupts the signal.

Thermal Shock / Cooling: Cold rain splashing onto a hot exhaust pipe and sensor can temporarily drop the sensor temperature below its operating threshold (around 600°F–800°F), or crack an older sensor housing, letting moisture touch internal components

Faulty Lambda Sensor: This is a very common failure point on the V85TT. Over time, the internal heating element or the sensor itself can fail. If the wiring is pristine, the Lambda sensor likely needs to be replaced.

Just as a note I had 2 new Lambda sensors in my shop.

A couple of weeks ago I bought one of these (iCarsoft MT V6 Plus Motorcycle Diagnostic Tool). This version works on 21 different brands of MC and has connecting cables for all.

So first I used the tool to read any stored codes and as expected I had the P0154 left cylinder. So I replaced the left side took for a 100 mile ride, no codes. Went to Chama NM this last weekend and again a crap load of rain. After the rain I started a ride got about 20 miles and the CEL came on and 10 or 15 seconds of misfire, then all seem fine  but the light stayed on. We did a lot of starts an stops along the 140 mile ride and at one point the CEL went out. Things were fine the remainder of the weekend.

Today I finally had time to take a look at stored codes, now I have a different code that is not a number code. This one says, "Right Lambda probe (functional diagnosis) no switching from lean". So now if I go back to my Google search it sounds like a bad sensor  and/or wiring.

Well as I proceeded to pull apart the wiring to replace the Lambda Sensor I pulling that connect from the Lambda Sensor to the wiring harness was severely corroded. Cleaned up things with DeOxit 5 and I also used some baking powder and vinegar to clean up the pin side of the connector and the rinsed with DeOxit 5. Put things together and plugged the diagnostic tool back in. I was able to read the data realtime and saw that both side were functioning. Button things up and did a 100 mile ride. Recheck with diagnostic tool and no codes.

Now I need to wait for the rain to verify.

Also I was able to reset my service wrench. 

So the iCarsoft MT V6 Plus Motorcycle Diagnostic Tool worked on the Moto Guzzi, and now I will start on the wife's F700GS, reset Service Wrench and try to fix her TPMS. So the $250 I spent on the tool has paid for itself and my nearest MG dealer is 100 miles away.