Now then gurus, my 2000 996 has developed a stutter in the 4000-5000 rpm range, when it feels way down on power, usually just when I want it. It also doesn't seem to rev freely from idle as welll as it did a few months ago. This seemed to coincide with, or happened shortly after I fitted a new fuel sensor. Spark plugs look fine and I've cleaned all the connectors, esp the timing pick up one on the LHS. I've not managed to check the TPS yet though - next on the list once I can get on to the pins. Bike has 50mm Termis and chip, and I've just fitted new Piper Cross air filters (the standard in-tube ones). It's had a few tankfuls of fuel while it's had the misfire, and the tank looks clean inside with no signs of water. I decided to try and hook up some diagnostic software so I downloaded DucatiDiag for old ECUs (think mine has the 1.6M), and also an open source tool written specifically for the 1.6M by a fella called TheDarkWraith. What a star. Unfortunately I can't get either tool to talk to the ECU. I know my cables and config are good as I've managed to hava a conversation with my Alfa, but the bike ECU is keeping shtumm. Any helpful suggestions much appreciated.
PeteW I recently had exactly the same problems by the sound of it on my 749s. I inspected all electrical connections as I had a hunch the symptoms were electrically related. Eventually after checking thorough everything, I replaced the fuel pump relay which is situated on the l.h.s of the battery- Problem solved. Relay cost £1.90 ( many thanks to ChrisW on this site for the heads up on relay problems)
Did you set the correct air gap on the ignition pickup sensor, that was diagnosed as a problem for me when I had a similar problem with my 998.
^ as above suits the symptoms at those revs and as John says it's a common trick to swap relays over located under seat (rather than 749 location) just to see if matters improve plus worth routinely checking all ignition related connectors for light corrosion. if you had said 3 - 4K then would have said 'twin injector stumble' more a possibility.
Thanks for the replies. I haven't changed the pick-up sensor Red so I don't think it will be that, and I don't think it's the relay either John. In fact it looks like it's the TPS. I've just being checking it and the resistance change (unconnected) with throttle angle doesn't track correctly, dropping and rising and then dropping again. Are they prone to failure? No luck with DucatiDiag yet Chris. By the way, is 'TPS Reset' available on the old version? I guess I'll need to do that if I fit a new one. Or is that fucntion not availble on that version?
TPS is not available as your bike uses the non-linear type. It is a multi-meter job to do the TPS on the old bikes
