MAP Sensors

[T250]

Bike started running a bit rough low down, no fault codes, so checked all the usual, tank filters, balance of TB's, TPS & STPS, lots of banging and popping on over run...started working and checking and could not find anything obvious, removed the TRE, no difference, swapped the MAP sensors over and that cured it!
Strange the resistance of each sensor was very close to each other, perhaps with different voltages the units acted incorrectly? 

If the one moved to the air box was faulty, surely that would create a fault on it's own?...Any ideas guys?
(Still not as smooth as it was, got to check the psi of the pump as the old chap is now 20 years old...)

[Hooli]

I'm guessing but I'd assume they've got something that moves with the pressure change inside, maybe a diaphragm. I guess that could get stiff with age so it doesn't change the sensor reading as much when the manifold pressure changes.

If I'm right then it'd read about right at static pressure so would work ok next to the airbox until you went up a mountain & it'd run rich.

[T250]

Think you could be right Hooli, if it is a diaphragm it would make sense for the one above the engine to probably get affected more, due to the location and heat from the engine over a period of time

[grog]

Theyre not cheap Mate. Just on $800 Aus plus freight for 2.

[Hooli]

I found aftermarket ones the other year, I can't remember the price but it was cheap enough. Think it was from a link on here.

[grog]

18591-42F00-000 part no.

[grog]

i looked up ridiculous prices for these sensors. Just crazy. They fit so many Suxuki models. I just bought 2 off 20k wrecked Boulevard, $50 delivered. Happy to have spares in cupboard. 

[grog]

Update, says now only has one, WTF. Anyway, 37 bucks for one is ok.

[T250]

Forgot to mention, it also affected the cold start, now from cold initial revs are 2K briefly, higher than the other sensor. I have ordered a second hand one from fleabay for £20, will give that a go when it arrives.