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mouse destroys temperature sensor

devo

Member
I returned from a trip to find a fine little mouse nest on top of my air filter shroud. The critter had chewed completely through one of the wires leading to the temperature sensor that sits on top of the air filter box. Will I hurt the bike by running it with the sensor disconnected? Thanks for any help!
 
The mice are everywhere!

I returned from a trip to find a fine little mouse nest on top of my air filter shroud. The critter had chewed completely through one of the wires leading to the temperature sensor that sits on top of the air filter box. Will I hurt the bike by running it with the sensor disconnected? Thanks for any help!

You didn't say what bike. If its a computer controlled-newer,fuel injected,cat converter I wouldn't. The system is so integrated the computer won't know what to do. I would guess the first thing to happen would be the check engine light to come on. I am not sure which way things will go but it will probably run way too rich-bad for cat-or way too lean-bad for engine. If the sensor was still connected and going bad the computer would keep adjusting to keep the engine happy and then set the code/check engine. If the wire was just chewed in half -after you strip the ends for a good connection- wire nut it together 'till you can get it fixed proper and watch for the check engine light.

BTW your not alone in the mice problem, I am still catching them daily around here. It used to be only going into the fall as they find a warmer place for the winter. I think now they are trying to escape the heat, and the red tail hawk. Good luck
 
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You don't say what type of bike? If its not hooked up on the early Motronic 2.2 it wll just tell the computer to use the default setting stored in the computer. You may have to play around with the choke and you may not just depends on outside temp when you start the bike.

This sensor has more impact when bike first starts from cold or on a restart. Once the bike runs for a bit then the cat senor plays a bigger role in feeding the computer information.

I've often wondered if this sensor gets dirty and should be cleaned. This sensor is like a poor man's version of a mass airflow sensor found in a car engine. They do get dirty and cause problems for the computer.

It would be really interesting to be able to know how the computer is mapped.
 
damned mice

It's a r1150r. I think there's enough of a pigtail left that I can bridge the wire, but about 2 in are just missing. Thanks for the advice, I won't run it until I cobble something together.
 
When the temp sensor in my old 91 K75RT went bad it made the bike run like it had a mix of gas and water in the tank. Really bad no matter what RPM. It was also not possible to just buy the sensor from BMW, they wanted you to buy the entire air box at over $675. I hope you can fix yours without having to replace it.
 
Sounds like you can-

It's a r1150r. I think there's enough of a pigtail left that I can bridge the wire, but about 2 in are just missing. Thanks for the advice, I won't run it until I cobble something together.

salvage it. On the sensitive stuff like that a good quality crimp connector with maybe some heat shrink over it. In the past I have soldered them-usually better-but I have come to suspect soldering the part caused it trouble. One of the other posters mentioned cleaning some of those type of sensors. It's good to match up the cleaner to the sensor-also RTV sealer if used-they have an odd sensitivity to products and I hate ruining a brand new one by using my favorite product.:cryDAMHIK
 
I'm currently running a 20k ohm resistor in place of my airbox temp sensor (R1100RS). The temp sensor is just a negative temperature compensation (NTC) resistor that has its resistance increase as the temperature decreases. The 20k resistor makes my bike run richer, which is what I want. You should be able to hobble along for a while with a resistor soldered in if you need.
 
good news?

You know, I was talking to my insurance agent today because apparently the mice also have eaten through the fuel line on my Ranger ($500!). Apparently, if you have comprehensive, that covers "rodent damage." Good to know. Anyway, I bought three traps, a sonic repeller, sticky sheets, and am contemplating a flame thrower.
 
mice

Cannot tell you what to do but can commiserate. Had mice build a nest in the air box of a '98 Honda VFR I used to have. A mechanic asked if the bike was running ok when it was in for service. I hadn't noticed a thing. My Beemer has a "screen" over the intake so not a concern there but I do worry about the little critters chewing through wires. Have scattered moth balls where I park in the garage to discourage them, and try not to let the bike sit for more than a few days at a time. So far, no more problems.
 
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