I just replaced the fuel pump on my '09 XB9SX because the old one would blow the fuse when it was hot (checked the wires and they werent chaffed, so had to replace). I got a new one from Fuel Performance and this solved the fuse issue, but now it doesn't run particularly well.

It used to get 40mpg+ and now barely 30mpg; and when accelerating hard or just cruising in 5th gear at 3500rpm it splutters a bit as if its not getting enough fuel. This has happened twice now on the motorway during the 300 miles i've done with the new pump - the first time when i pulled over it continued to splutter for a few seconds while idling on the hard shoulder, and the second time just dropping below 3000rpm stopped it so had to limp home.

Would changing the fuel map help this? Or this is a physical issue? I don't have any experience with ECM Spy.

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Life moves pretty fast. If you don't stop and look around once in a while, you could miss it.

and by the way, at the same time I changed from the standard 08+ headers and exhaust with a cat, to early headers and a Drummer exhaust. It doesn't pop or anything so I didn't think it was running too rich.

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Life moves pretty fast. If you don't stop and look around once in a while, you could miss it.

If you changed the headers I'm now wondering if your issue could be 02 sensor related ,they don't always throw up a fault code.

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2001 X1 2009 1125CR 2006 Uly X3 2010 Uly a fully Maz'd S1 and a 1991 RS1200 Westwind.

Hmmm... I did make sure i didn't contaminate it, or damage it. Is there any simple way to test it?

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Life moves pretty fast. If you don't stop and look around once in a while, you could miss it.

Did you change all the o rings?

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08 Specialized Langster

Nope. I wouldn't have thought it would particularly need changing on the O2 sensor. Do you think it could be leaking, and therefore reading too much oxygen, and therefore adding more fuel? Is that how this sensor works?

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Life moves pretty fast. If you don't stop and look around once in a while, you could miss it.

O rings on the pump

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08 Specialized Langster

oh, no i didn't but i put a little grease on them and it went back in without snagging, and i've checked for leaks.

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Life moves pretty fast. If you don't stop and look around once in a while, you could miss it.

I think I would have changed them whilst I was there.

Best thing to do is check your fuel pressure...

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08 Specialized Langster

I would have too if I had known to buy some before it was out in my hand.

How so I test the pressure? It also doesn't happen ALL the time at high revs, so it's inconsistent.

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Life moves pretty fast. If you don't stop and look around once in a while, you could miss it.

Inconsistent you may feel it is, it's easy to check and eliminate from your enquiries...

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08 Specialized Langster

1st rule of fault finding: Don't assume that the new part you've just fitted is necessarily working correctly.

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'98 M2 Razorback, it's a keeper.

ok, so how do i check its pressure? Just disconnect the fuel hose and see if it squirts in my eye?

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Life moves pretty fast. If you don't stop and look around once in a while, you could miss it.

and only change one thing at a time and test afterward

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Buell Ulysses XB12X 06/08

Yeh I know, but that's not always possible, when on a buell all the parts break, and at the same time.

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Life moves pretty fast. If you don't stop and look around once in a while, you could miss it.