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CO sensor, what is it?


rol1

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I have a wrecker auction 96 1100rt, without a key. So I bought a Speeduino. One of the inputs is the MAP sensor. Is this anything like the CO sensor? I see the vac lines from the underside of throttle body to the left side sensor. What is the CO sensor? How does it work? 
   
Is CO concentration of oxygen? Another way of saying MAP sensor?wiring_overview.png

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dirtrider
17 hours ago, rol1 said:

I have a wrecker auction 96 1100rt, without a key. So I bought a Speeduino. One of the inputs is the MAP sensor. Is this anything like the CO sensor? I see the vac lines from the underside of throttle body to the left side sensor. What is the CO sensor? How does it work? 
   
Is CO concentration of oxygen? Another way of saying MAP sensor?

Afternoon  rol1

 

No, they are different sensors.

 

The MAP (Manifold Absolute Pressure) is a vacuum sensing sensor (BMW 1100rt doesn't use one). The BMW Co. sensor is basically NOT a sensor but is an idle Co. trim potentiometer (mechanically adjusted resistor) that is used on older BMW bikes to set the Co. levels going out the exhaust at idle (is ONLY used on motorcycles without an o2 sensor plus it needs to see NO CCP, or a non U.S. CCP ).

 

The vacuum lines going to the  L/H side on your 1100rt are going to the emission Evap. canister purge solenoid not a MAP sensor. 

 

You will have to call  Speeduino about using a MAP sensor on a BMW boxer twin as the 360° firing 2 cylinder boxer has very harsh & wildly pulsating vacuum pulses (not the best source to get a stable MAP output signal). 

 

Your BMW 1100rt boxer uses an  Alpha-N fueling control system so never used a MAP sensor. 

 

The 1100rt doesn't use an anti-theft key system so you can actually remove the ignition switch key barrel then use a screwdriver to turn the ignition on (or buy another ignition switch & key on E-Bay).   All the Motronic fueling computer needs to start & run is proper 12v power to the correct pins & all the engine sensors hooked up &  working. 

 

   

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Then I can jump the plug in the harness and crank it up? The switch has 5 wires according to the electrical schematic, red, green, violet, gray and grey/blue?? 

C405C6B8-9562-4C1A-AB78-3639D909E978.png

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12 hours ago, rol1 said:

Then I can jump the plug in the harness and crank it up? The switch has 5 wires according to the electrical schematic, red, green, violet, gray and grey/blue?? 

 

Morning  rol1

 

Yes, just jump red to green, then with kill switch ON, side stand UP, transmission in neutral it should then start & run. 

 

But the ignition switch has more outputs that power other items like the brake light, headlight, dash gauges, etc so keep that in mind. 

 

There is a small set screw on the ignition switch barrel assembly (usually under some red sealer). If you dig that sealer out then remove the small screw you can drop the actual bottom switch part down out of the upper barrel assembly then the removed switch can be operated with a proper fitting screwdriver or something.  (this powers all the required circuits when turned on)

 

MuzvBa0.jpg

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Back to the CO Potentiometer is not a sensor. The small rubber line from each TB that join together and runs to the left side by the fuse box is to the charcoal canister? Part of the emissions stuff?

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34 minutes ago, rol1 said:

Is the setscrew a flathead? Less room to get a direct shot around the forkleg. Looking for a shorter screwdriver. 

 

Afternoon rol1

 

It is set screw, but with a flat blade screwdriver slot instead of an allen hex. 

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40 minutes ago, rol1 said:

Back to the CO Potentiometer is not a sensor. The small rubber line from each TB that join together and runs to the left side by the fuse box is to the charcoal canister? Part of the emissions stuff?

Afternoon rol1 

 

The small rubber hoses run from each throttle body nipple to an electrical/vacuum solenoid  (BMW calls it a fuel tank breather valve)  on the L/H side. Then from the electrical/vacuum solenoid a hose runs back to the right rear of the motorcycle to the evap canister (charcoal canister). If your bike still has one as a lot of those were removed by previous owners.

 

This is mainly a USA emission thing as most other countries didn't have that charcoal canister set up.

 

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Tried jumping the grn and red, but no fire. Don’t smell gas at the exhaust. 
 

Do non canister bikes have the nipple for potentiometer on the TB? Ir just for our market? 
 

Now to pull the plugs without the list of special tools. 

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Morning  rol1

 

Tried jumping the green and red, but no fire. Don’t smell gas at the exhaust.-- Is the side stand UP??  Can you hear the fuel pump run for about 3 seconds when you jump the red to green?   

 

How long did that motorcycle sit before you bought it? If it sat for a long time then the fuel pump might be stuck or corroded up. 

 

Or the insides of the fuel tank could be all gunked up with old fuel or stale-fuel varnish.

 

If you don't hear the fuel pump run for 2-3 seconds at first red to green jump then you need to find out why. The pump should run for 2-3 seconds at red to green jump then it will quit until engine is cranking so should start running again at engine cranking.  


If the pump runs then you need to check for actual fuel flow at the fuel return hose coming from the rear  (if no fuel flow then you need to find out why.

If you DO have fuel flow coming  out of the return line coming from the rear then you need to make sure your fuel injectors are electrically triggering (a NOID light works best for this) 

 

LOTS of things could be wrong with a BMW boxer bike that has been sitting for a long time, so you need to work your way through them one at a time until you find the problem, or problems. 

 

 

Do non canister bikes have the nipple for potentiometer on the TB? Ir just for our market? -- All the 1100 Throttle Bodies have the vacuum nipples on them, on US (emission compliant) motorcycles those nipples have hoses going to the purge solenoid, on non US emission compliant 1100 bikes those nipples have rubber vacuum caps on them to plug them off. 
 

Now to pull the plugs without the list of special tools.-- You can just use a thin-walled 16mm (5/8")  standard spark plug socket or even use a standard 16mm (5/8") deep socket--  (must be thin walled socket to fit through the valve cover hole) , or worst case just remove the valve covers then the spark plugs are more easily accessible.

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