Rear Vacuum sensor

I've recently been working on getting my SD back to full fitness, I had her running fine yesterday after a new installing a new battery.
Today I went to mess around with her some more, and when I started her up, she was running very lumpily and idling at low revs.
The idle gradually raised to a normal level and then I got a fault code 69 for the rear vacuum hose.

I unplugged the sensor and she ran perfectly, but replacing the sensor brings back the fault. A replacement sensor looks to cost £80!
Anyone know of a cheap fix, or do I have to throw down the cash for a new one?

I bet you can pick up a cheapy off the KTM forum dude.

If its the 1 that reads the pressure of the small tube that comes from underneith the rear throttle body? Then swap it with the air pressure sensor that sits inside the headlight mask!

They are exactly the same and unless the the sensors completly knackered it should do the job as the air pressure sensor OK

Gents
To add to this..I've done my motobox and plugged off all the vaccuum lines at the throttle bodies removing the canister....Of course I get both codes for vacuum..I think 68 and 69...Any way around this..???
Cheers
Mike

If that doesn't work, try to read some information of the sensor itself and google it. They are a electronic unit that might be fairly common and you might be able to order it from a supplier like RS or so for half the price.
Good luck and keep us posted if you find an alternative supply.
Eastern beaver in Japan could also be of help as he supplies bike specific electrical connectors and bits.

What's the bet that there is just some oil or moisture in contact with the sensor... Degeaser wash then dry off

Well I swapped over the sensors this morning and the problem is still there. The vacuum hose itself is clear with no blockages.
Anyone have an idea of what could be wrong?

I'll have another in depth look over it tonight, and check the connections. They should be ok, as I used electric grease on them, perhaps a wire has been split.

Check the pipe for cracks/leaks, if its pulling in extra air it will throw a wobly!

If theyve been swapped and the fault is still there then the sensor must be OK (but just out of interest swap the front and rear sensors and see if the fault code moves to the front cylinder!?)

FFS Problem solved! When messing around with the BGC I noticed I had accidentally pulled the hose from the front vacuum sensor behind the radiator. As soon as I reconnected it, the bike started up normally. Now if only the FI light had told me it was the front one causing the problem!

Oh well, at least its fixed