Map sensor relays

Bike has been running poorly especially when warm I think, feels like it's not getting the fuel right, not very bad but enough to be noticeable.
I checked the coils and plug leads as best I could, I read somewhere that a faulty Map sensor on the airbox could cause this issue, anyone any experience of it happening before?

 

If any of the sensors are giving dodgy inputs that will normally trigger a FI fault and illuminate the light. The MAP sensor certainly know whether it is exposed to intake vacuum or not if you leave it's hose unplugged!

There's a good troubleshooting guide at the back of the service manual that will walk you through a diagnostic procedure.

 

Thanks Terry, I suppose it's not a faulty map sensor so, if it was it would likely be putting on the Fi warning light.
It's not very bad, just a bit annoying, I've put some fuel additive in the tank, 'Redex' maybe it will help clean her out.
There are no real good bike mechanics around here, most just want to do the easy servicing type work, not many would fancy or be able to diagnose this problem in my Vfr, maybe I'll find one sometime, in the meantime I'll just ride her as she is, it isn't terrible.

 

I'm sure there's also "partial" failures which are annoying but don't represent a complete fault. I'm thinking about air leaks in the vacuum hoses which reduce the vacuum signal but not enough to trigger a fault. The hoses to the MAP sensor come from each intake port and join at a 5-way connector with a hose from there to the sensor. There's also the hose that connects to the fuel regulator which may perish and leak. Both conditions would throw off the fueling a little; a reduced MAP vacuum would lead to leaner running, and a leaking FPR hose would lead to over-fuelling.

Based on your symptoms, I wondered whether you had a fuel pump/filter problem that works OK at low flow but can't keep up when things are warmed and you wind up the throttle a bit.

 

I have no idea Terry and no way of finding out really so I'll just ride her as she is for now, I'll keep that in mind though if I ever find a good mechanic I'll mention it to him. Thanks.

 

I highly recommend ditching as much of that vacuum hose as you can and upgrading to a quality thick wall hose. Cap all the unneeded vacuum ports. It limits the potential fuckery of vacuum leaks.

 

I think our bikes may inhabit parallel universes...it certainly looks cleaner in yours...The red hoses certainly make them easier to trace.

 

Changing the air filter is about the limits of my mechanical abilities
Got a tip to remove and spray clean the Map sensors with air flow sensor cleaner, think it's worth a try, I can mange this hopefully