Hello
I am putting a wrecked 03 monster 800Sie back together. The Throttle position sensor was broken so I replaced it. I backed the throttle stop screws off completely and set the TPS to .148-.150 volts. I then moved the throttle stops back to where they were. I hooked up my VDST turn on the ignition (did not start it)and went to the tps icon in the VDST and hit reset. On the VDST gage display it now says 2.4 on the TPS block. The bike is still not running correctly although, better than it was, as it is running I intermittently miss on one of the cylinders. Both plugs are black, the vertical looks better than the horizontal. (new plugs, same as the old plugs). Before doing the TPS reset there was a code (P0120 Potentiometer sensor 1 open circut. now there are now error codes.
Did I set the TPS correctly?
thanks
dan-o
800 has a linear tps, the old 150mv procedure does not apply. you now need to get the throttle stops back to where they were to give 2.4 degrees opening.
http://www.bikeboy.org/ducatitps.html (http://www.bikeboy.org/ducatitps.html)
All I did with my 800 (5AM ECU) was hook up VDST, open up the throttle and snap it back, and reset TPS. By the way Brad, I followed your instructions in an earlier thread for valve adjust->throttle body sync-> TPS reset -> CO adjust in that order, and now I have a brand new bike. Kinda makes me think that there are a lot of people out there with Ducatis that aren't running correctly, thinking that's 'just how it's supposed to be'. Thanks for your advice.
Listen to Brad, he's smarter than me but...
If you turn the key on but don't start the bike the ECU can 'go to sleep'. This is why if you turn the key but don't start it for 10 seconds it won't start no matter how much you crank it. Just turn the key off and on and you've got ten seconds to start it again.
I don't know if this would keep you from reseting the TPS but to be safe I always start the bike then kill it with the red engine switch, then turn the switch back on but do not restart, reset TPS, then restart. My VDSTS with USB/serial adapter can take a while to connect to the ECU so this way I figure I'm covered.
Scott
Wow. lots of info, thanks to everyone who responded. After reading thru this I think I may have the wrong TPS the one I have has the slots for adjustment. I don't know if this will make a difference but, I am going to dive back in and reset the TPS the way it should be. Thanks again
dan
If you have the wrong TPS it will not work, the two types are not swapable. You should have the linear one for an '03 800. I have the '03 800 Dark so I'm familiar. You can't set this by adjusting voltage, you need VDSTS or similar.
You might want to pop onto theDucati site and pull down the exploded diagrams for your year and model. Compare that part number with the number on the part you have. If it's wrong take it back.
Scott
Hi Scott mine says PF3C/00 -2860DAE what is on yours?
No idea, my bike is not here. I can check later when I get home. Go to the official Ducati sight and download the exploded parts diagram for your bike. Check against that part #.
Scott
if it has slots it's nonlinear.
I'm just not getting this. Hope it's not too much of a threadjack. My 2003 M800 Dark has an unslotted TPS. Can I, and if so should I, adjust the TPS with, or without, a VDSTS? My understanding of Brad's work suggests that no adjustment is necessary. Thanks for any insights.
Quote from: Mr Earl on October 01, 2009, 07:14:00 PM
I'm just not getting this. Hope it's not too much of a threadjack. My 2003 M800 Dark has an unslotted TPS. Can I, and if so should I, adjust the TPS with, or without, a VDSTS? My understanding of Brad's work suggests that no adjustment is necessary. Thanks for any insights.
You need a VDSTS or similar to set the TPS. If the TPS was set properly at some point and no one messed with the throttle stop screw after that, all should be good.
the tps is set at the factory during initial tune set up after assembly. i've seen only one bike that i can think of that needed a tps reset at pre delivery - it was an 800m that ran very badly down low.
i reset it at service just for the sake of doing it as it's easy when you've got the gear and it's hooked up anyway, but apart from that you really only need to do it if you replace the tps or the ecu.
if you replace a tps you screw the new one on without any real attention to where it is sitting (rounds holes have minimal movement anyway), do a reset via the electronic diagnostic tools and away you go.
the linear tps has a smaller output range too (lower max voltage), so if you fitted a non linear tps the ecu would think it was at full throttle before the butterflies got to wot, and would run rich overall i'd think due to the different curve gradients.
wow, brad black is absolutly correct. I do have a non linear one on mine (just ordered the correct one) and it was running way to rich (black plugs) So just to be as accurate as possible, All I have to do is replace the TPS and make sure the throttle position is 2.4 and reset with my VDST?
thanks
dan
Correct me if I'm wrong Brad but...
You screw it on and connect the wires. You don't measure anything with a volt meter ever. You connect VDSTS and do a TPS reset. You're done with the TPS until your next service, move on to other things
Non-linear TPSs are used to measure absolute position, that's why you need so many mV at throttle closed. Linear TPSs measure relative position. Wherever it is at the start (throttle closed) is fine so long as the ECU knows what that is. The TPS reset with VDSTS says to the ECU, "Look at the TPS right now, call that throttle closed and measure from there." The absolute voltage/resistance is not important, just how much it changes from where it started.
If you really want to know more about it I can post up a much more technical, detailed, and long explanation of linear and non-linear TPSs and how the ECU on a Ducati works with them but you can probably already find that info if you look around Brad's website. That's probably where I learned it in the first place. While you're there read his two part explanation of how fuel injection works. Clearest explanation I have ever read.
Scott
Got the correct TPS on the bike today, after setting it with the VDST, went for a ride, it now runs very well. Thank you all for the help!
[bow_down] [bow_down]
dan-o