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Cooked Lambada sensor anyone??

2155 Views 23 Replies 8 Participants Last post by  shush319
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I got Fault/Blink code 45 (O2 heater) when I started the bike to go home from work yesterday. I'd say she's cooked..... Thought the FuelX would keep her running properly in closed loop, but this damage could very possibly have been done before I changed the fuel injector to the Gray Area KTM injector or installed the FuelX, & the FuelX never could get a proper O2 reading..... Never seen one this white before, no wonder she's been running hot!

Side note..... Stock replacement is $169 USD, for an O2 sensor!!!!! To he** with that! I found a Bosch replacement from a Pontiac on Amazon with the same color wires for $48 shipped, will be here tomorrow. Just need to de-pin the plug and insert the pins into the factory plug.

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Smokin Hot !

Yea she looks she’s been running a tad warm. You’d certainly have been concerned if you’d done a ‘plug chop’ on a 2-stroke and found that colour plug !

Fingers crossed: your new Lambda sorts all and its the end of that.

Meanwhile; any way of checking current AFR’s now that you’ve perhaps had a ‘warning’ ?

Good luck.
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Smokin Hot !

Yea she looks she’s been running a tad warm. You’d certainly have been concerned if you’d done a ‘plug chop’ on a 2-stroke and found that colour plug !

Fingers crossed: your new Lambda sorts all and its the end of that.

Meanwhile; and way of checking current AFR’s now that you’ve perhaps had a ‘warning’ ?

Good luck.
RIGHT! Would have jumped 8-10 main jet sizes if I saw a 2t plug that color..... LOL

She's sitting until I get a new sensor on her. Will be keeping an eye on the AFR when I get the new one installed for sure.

Figured I needed to dust off this beast in the meantime, she mostly gets neglected on the streets anymore.....

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RIGHT! Would have jumped 8-10 main jet sizes if I saw a 2t plug that color..... LOL

She's sitting until I get a new sensor on her. Will be keeping an eye on the AFR when I get the new one installed for sure.

Figured I needed to dust off this beast in the meantime, she mostly gets neglected on the streets anymore.....

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Yes ! Probably for the best to rest the Duke until new Lambda is in; AND you’ve had a chance to look into the ‘Why’ more to the point….

Very very nice the R6 ! Probably too much for me these days 😳 This a Track bike now primarily I take it ? Heavily modified or ? What Tracks do you ride / are you near ?

I’m back into bikes after 6 years or so without one for whatever reason.. But the little Duke has gotten me the bug back again.
Infact just spoken to my insurance company tonight. And they do multibike policies. So I think I’m about to add a road legal ‘dual sport’ of some flavour to the garage; to do some light off road / exploring with…..

Stay safe 👋
Yes ! Probably for the best to rest the Duke until new Lambda is in; AND you’ve had a chance to look into the ‘Why’ more to the point….

Very very nice the R6 ! Probably too much for me these days 😳 This a Track bike now primarily I take it ? Heavily modified or ? What Tracks do you ride / are you near ?

I’m back into bikes after 6 years or so without one for whatever reason.. But the little Duke has gotten me the bug back again.
Infact just spoken to my insurance company tonight. And they do multibike policies. So I think I’m about to add a road legal ‘dual sport’ of some flavour to the garage; to do some light off road / exploring with…..

Stay safe 👋
Yes, definitely a SuperSport track bike build (full Yoshi system, BMC filter, velocity stacks, and ECU Dyno tune/flash, stock other than that). I use to race her before I started breaking lots of bones on other bikes on the streets..... Daytona, Roebling Road (Georgia), and JenningsGp (North Florida) are the only tracks I've ridden her on. Got P2 @ Daytona the 1st time I took her there :cool:

Pretty sure I started the cooking process when I shaved the head and installed the thin head gasket kit, after the head gasket blew out @ 6k miles. I did not install the FuelX until after I added the GAKTM injector (300cc flow rate vs stock 186cc), so I really don;t know when it started going out, but that's my best guess.
What does your spark plug look like?
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That would be my first thing to check.
If the GA injector squirts almost twice the amount of fuel I'd check that as well.

What does your spark plug look like?
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What does your spark plug look like?
HA! I thought the same thing, but have not had the motivation to take half the bike apart to get to it!!! Found a Bosch GM O2 sensor works perfectly as a replacement for the OEM, and only cost $48 shipped VS $169..... Just needed to de-pin the GM plug and insert the pins into the Duke connector. LINK to O2 sensor if interested. Just got it installed and cleared the codes, works perfect.

Also found I am getting odd readings on the Torque app for AFR with the FuelX installed. Like the maps are backwards from what they should be 10 is 1, and 1 is 10..... Lower #'s are richer, higher #'s leaner! In the middle of figuring that out with support.... See screenshots here if interested (each photo is labeled if you open it).
What year is your duke? I can remove my plug without pulling the tank. I just slip the tool in and pop it out.
On my first gen. I need to loosen the 4 radiator nuts and pull the radiator forward about 3 cm to unscrew the O2 sensor.
Nothing else needs removing.
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What year is your duke? I can remove my plug without pulling the tank. I just slip the tool in and pop it out.
2016.....
On my first gen. I need to loosen the 4 radiator nuts and pull the radiator forward about 3 cm to unscrew the O2 sensor.
Nothing else needs removing.
Yeah, O2 sensor is easy, spark plug, not so much.
I pull my spark plug all the time on my first gen. You just need the right combo of tools. I use a socket and a 3 inch extension. Then I just a magnet to get the plug out.
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Spark plug tool from the KTM tool kit, a breeze.
As others said I am concerned for something more than your lambda sensor, with that color. The Air Fuel Mix should be checked, Compression/leak down must be checked. An experienced dealer or repair store must check the bike.

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Hi,I have seen sensors like this,a few years back in UK we had a problem when a fuel company overloaded fuel with to many additives,cars where breaking down with lambda faults,when removing them they were white like yours,parts companies had sensors on back order so did the dealers.i have also seen this when an engine is burning a bit of oil or coolant,also could be an over fuel,but it could have over fuelled due to a bad sensor.as others have said might be worth getting checked when you have new sensor,if you have changed other parts the fuel air mixture could now be wrong.
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I pull my spark plug all the time on my first gen. You just need the right combo of tools. I use a socket and a 3 inch extension. Then I just a magnet to get the plug out.
I will have to take a look to see if I can replicate the process later.
As others said I am concerned for something more than your lambda sensor, with that color. The Air Fuel Mix should be checked, Compression/leak down must be checked. An experienced dealer or repair store must check the bike.

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I will NEVER have one of my bikes at a dealership, those idiots could screw up lubing a chain!!! Compression & leak down were checked after I shaved the head flat and replaced the stock blown head gasket with a thin head gasket kit, both before initial start up and after 150 miles or so.

Hi,I have seen sensors like this,a few years back in UK we had a problem when a fuel company overloaded fuel with to many additives,cars where breaking down with lambda faults,when removing them they were white like yours,parts companies had sensors on back order so did the dealers.i have also seen this when an engine is burning a bit of oil or coolant,also could be an over fuel,but it could have over fuelled due to a bad sensor.as others have said might be worth getting checked when you have new sensor,if you have changed other parts the fuel air mixture could now be wrong.
I can see variances in fuel, but not to that extreme. I do occasionally run a tank of non-ethanol through it to keep things clean and tidy. I have to assume this will affect the FuelX that is supposed to be "Auto-tuning" the closed loop, but should be within it's capabilities to "Tune on the fly" as they claim. Normally run 93 octane from 2 different stores close to home, unless I am out on a long ride. Before this failure I had been on a LONG ride that required 3 fill-ups from 3 different (not my usual) stations, so I could very well have gotten some funky gas that day (2 days before the sensor failed completely).

I am still leaning towards having already done most of the damage to the sensor after the head gasket repair, and before I got the Gray Area KTM injector installed. I am monitoring AFR on EVERY ride now to see what it is doing so I can try to catch it running lean if it does. So far with the new sensor, all seems good.
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If you don't trust the dealer, at least try someone professional with a lot of experience.

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If you don't trust the dealer, at least try someone professional with a lot of experience.

Sent from my A80Pro using Tapatalk
Why would I start letting someone else touch any of my bikes at this point? Only person to ever touch one of my bikes was my father when we raced flat track in the 70's, now he's in his 70's and I wouldn't let him touch any of my bikes. Not everyone needs someone else to do things for them, I am perfectly capable on my own. If there is anything I do not know about, I know how to read and understand what I have read. Feel bad for you if you cannot.....
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