using 25% more fuel

Wreford Miles

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Since back from it's service my 1150 is using around 25% more fuel.

It had the fuel filter changed

It's been cutting out but didn't miss a beat riding home from llangolen

the exhaust is black

it runs well

any ideas?


Thanks
 
Contact whoever did the work and ask them what they did.
Did they adjust the TPS?.The fueling maps are partly controlled by this.
Increase the voltage,more fuel gets thrown in.
Does it have the quick-disconnects.Replaced "o" rings?.
 
I agree check the TPS setting, ideal is 371mv with a closed throttle.
 
Pull the rubber sleeve back from the electric plug.

Connect a voltmeter between (I think if I remember correctly) the two outer terminals. ie 1 and 4 (hmm you'd better check because it could be 2 and 4:rolleyes: )

You can do this by pushing the 'probes' of the multimeter up into the connector block. Some use a pin pushed through the insulation of the wires but thats not necessary.

Turn ignition on and make sure your fast idle is not on, the throttle needs to be at tickover/idle.

The voltage should be around 371mv. I believe the standard setting is around 365mv but that's possibly to keep emissions down, it runs better at the slightly richer setting ie 371mv.

If not slacked slightly the two locking screws and very lightly tap the TPS body either way until it gets a satisfactory reading.

Then open the throttle to check the the voltage is increasing, if it doesn't the TPS may be faulty.
 
Thanks guys....how do you you check the tps settings?

meter between the rearmost wire on the TPS connector block & earth with the ignition on.

i find the easiest way to do this is to pull off the rubber boot & stick a pin inside the connector alongside the wire. attach meter lead to the pin.

i'm guessing it's not the TPS though, too much fuel increase. TPS doesn't recognise settings over 400mv & i know 390mv or so works ok :nenau

i'm a big fan of 385mv :)

i'm thinking temperature sender stuffed so that the ECU thinks the engine's cold all the time, or lambda probe disconnected/stuffed.

those are wild guesses though, nothing scientific & not exactly common problems :augie
 
the bike used about 40% more fuel today on Clives White Horse ride...

It ran well on the way down holding a nice steady ton two up.

On the way back it was quite rough as though it was miss fireing and losing power... keeping it accelerating would solve it but kept having to slow down!
 
Sounds a bit like a spark plug cap breaking down, that causes the stuttering and with the slight drop in power means more fuel used. Check that the leads are on the spark plugs properly.
 
the bike used about 40% more fuel today on Clives White Horse ride...

It ran well on the way down holding a nice steady ton two up.

On the way back it was quite rough as though it was miss fireing and losing power... keeping it accelerating would solve it but kept having to slow down!


Your symptoms sound exactly as were Jinxy's std 1150 in Morocco last year.
He was getting around 80 miles to the tank and his left hand pannier was covered in soot.

We had all sorts of advise to check this and swop that over the phone, but it was definately a faulty TPS.

When I checked it with a multi meter the voltage was way out and didn't change when I moved the TPS unit throughout it's range.
I proved it by fitting mine to the bike and it ran perfectly.

a 2nd hand one from Sherlocks is not expensive, around £40

I hope yours is that simple:) but of course it could just be the HT lead:confused: :D
 
Your symptoms sound exactly as were Jinxy's std 1150 in Morocco last year.
He was getting around 80 miles to the tank and his left hand pannier was covered in soot.

We had all sorts of advise to check this and swop that over the phone, but it was definately a faulty TPS.

When I checked it with a multi meter the voltage was way out and didn't change when I moved the TPS unit throughout it's range.
I proved it by fitting mine to the bike and it ran perfectly.

a 2nd hand one from Sherlocks is not expensive, around £40

I hope yours is that simple:) but of course it could just be the HT lead:confused: :D


that sounds like a plan.
 
Ok might be a little stupid, but a mate had the same sort of problem on a SV, bike used way too much fuel, kept stalling if left on idle, exhaust was black. We took it apart, changed or checked 99.9% of the sensors and in the end it turned out to be the throttle balance was off. As soon as we corrected it, the bike ran like a dream
 
erm....just been serviced ..???

throttle balance or air screws - 90%

either done badly or improperly

yes - it could be a TPS..but why would it go after it had been serviced. ??..10%


make your own manometer and ATF fluid to do an instant check.
 
erm....just been serviced ..???

throttle balance or air screws - 90%

either done badly or improperly

yes - it could be a TPS..but why would it go after it had been serviced. ??..10%


make your own manometer and ATF fluid to do an instant check.

I think the throttle balance screws are the brass ones on each throttle body...

Well I took these out today on the advice of Motoworks because they said a little bit of gunge on these could cause problems.

They where overed in gunge, loads of it.

They've been cleaned, new plugs have been fitted and it still runs rough so i've put some injector cleaner in the tank.

Q; what would cause so much gunge?
 


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