| Author | Message | ||
     Paul_in_japan |
Long story short- My '05 XB12R 13700km went in for a service (primary chain/TPS reset/clutch etc). It came back running horribly ,fluctuating revs at idle, creeping up to 1500RMP then dropping to 900RPM, the REVS sometimes hanging high after running then dipping low. SO I took it back to the shop today he re-did the TPS, fiddled with the idle and says it looks OK try that. I went to leave but the REVs had dropped back to 900RPM again so he wheeled it back into the shop. Plugged it into the computer again which shows the TPS figure rising and falling on its own with the bike just idling (4.8 up to 5.2 etc.)The mechanic shrugs his shoulders and says "mystery". He checked for an intake leak but says it isnt that. Something wrong with the TPS itself? any ideas of what it might be so I can help point him in the right direction? he doesn't have the benefit of Badweb. anyone had the same problem. | ||
| Buellinachinashop |
It takes a few miles for the ECM to learn the adjustments. I had the same thing happen wafter a TPS reset this summer. I put on about 100 miles before everything evened out. | ||
| Hammer71 |
Check the idle adjustment cable. Have seen numerous ones that will bunch up a bit and will cause erratic idle just by moving it back and forth. | ||
| Id073897 |
It came back running horribly ,fluctuating revs at idle, creeping up to 1500RMP then dropping to 900RPM, the REVS sometimes hanging high after running then dipping low. Even in idle, lambda correction is active by default. Lambda correction always starts at the AFV and then walks in the direction needed, until the ECM recognizes a too rich or too lean mixture (depending on the starting point of the lambda correction). Then the correction jumps again to AFV and a new cycle starts. What you get is a sawtooth shaped curve and the revs follow this curve also. This happens always, but if the AFV is too much away from what it should be (due to environment and configuration), e.g. after an AFV reset, then this effect gets very visible. If it's really annoying and doesn't stop after calibration, you might try to switch off lambda correction in idle and adjust mixture as required. The "hanging" rev might be caused by a rapid change in spark advance at low throttle around 1500 to 2000 rpm. You could try to reduce spark advance at this point for a small amount and watch, if this helps. Regards, Gunter | ||
| Barker |
Try this in this order. 1. Ride on flat ground 5 gear 3000 to 4000rpm for 5-10 minutes. (this should reset AFV value) 2. Reset TPS corectly. Then repeat 1. Most dealers don't rest the TPS correctly. Correct TPS reset involves. Bike fully warmed-up. Back out idle adjustemt so the throttle sticks closed. Reset TPS Then set idle to 1050rpm. You can replace the tps if you want. Buy the cheaper aftermarket mustang part. Mine was $12. All the of FI is ford parts. Except the O2 sensor it a a chevy part. (Message edited by barker on December 17, 2007) | ||
| Firebolteric_ma |
 There lies the problem....YOU brought it to the dealership..... Even after a TPS reset the bike should run fine, But it is wise to run the bike a few miles at 3-4k...... Any Badwebber's near you who could do it for you?...The CORRECT way? I do anyone near me/Nebo Crew for free... | ||
| Skully |
The TPS is not a "learned" value like the Adaptive Fuel Value is and therefore running the bike has no effect on it. The TPS value should not be fluctuating. Period. The throttle position sensor (TPS) may have issues and is easily replaced. Keith | ||
| M1combat |
I agree with Skully. If you can see the voltage from the TPS fluctuating there's something wrong with it (as long as you weren't moving the throttle). Check it with the bike off and move the throttle slowly. See if it fluctuates while the throttle is moving as well. Sounds like a bad sensor to me but I don't know. It's just a potentiometer as far as I know. Look them up on the wiki. | ||
| Paul_in_japan |
Thanks for the quick replies- The bike was ridden about 300+km between the service and taking it back to the shop. Its nearly impossible to find 10mins of flat open 3000RPM road here but I thought the AFV might have sorted itself out over the 300km. He said the AFV was at 105% when I bought it back (I dunno what that means). As for the TPS fluctuation I was a bit skeptical too. Chicken or the egg. Is the TPS broken or is it reading correctly but something else (eg. a bunched up vibrating idle cable) causing the fluctuation and the TPS is just doing its job. I can't imagine there is much visual difference between 4.8 and 5.2 in TPS. Ill go back today and see if he has made any progress. cheers everyone. | ||
| Sgthigg |
Paul I agree with barker. This is how it is supposed to be done. When the Tech "fiddled with the idle". I will almost guarantee he did not reset it at that point again correctly. Wich means it is not reset. If the TPS is not set right as step 1. It will NEVER be right no matter how much the tech plays with it. Good luck, Like I said anytime you want to head down this way I will do it for free. I am actually looking at building the cable and downloading the ECM spy. If you want once I get that up and running I will sell you my VDSTS,Palm and the cable very reasonably. The offer still stands anytime. | ||
| Skully |
An Adaptive Fuel Value in the 95-105 range is perfectly normal. A vibrating throttle cable will not cause the TPS to fluctuate or you would never be able to reduce the idle enough to zero the TPS (the cable would be binding) Keith | ||
| Id073897 |
From TP 4.8 to 5.1 (I suppose degree) is just one bit difference if you look at the raw digital value - on my bench from 14 to 15. So no reason to worry about that, it's perfectly normal. This might be caused by the A/D convertor if the voltage is just at the boundary. The change in fuel regarding to the fuel map is neglectable (if even noticeable). Regards, Gunter | ||
| Treadmarks |
At idle, the throttle body plate bounces slightly due to the pulsations from the opening and closing of the intake valves. It is important to eliminate any play between the throttle plate and the TPS. Here is how to do it: Guys, Here is the deal on the solid TPS reset. Think of the TPS as a spring loaded pot. It sends a voltage signal to the ECM and it adds fuel accordingly. Very simple really. The entire process is actually based on the starting point of the TPS in relation to the throttle plate. The TPS has two plastic index tabs that must line up with the tabs on the throttle plate shaft. It seems most TPS sensors are installed straight up from the factory and this is ok for a while. After the bike is broken in, these tabs get a small amount of wear on them and they are no longer properly timed with the true zero of the throttle plate. This is when everyone runs to the stealer to get their TPS reset. It is the combination of wear on the TPS tabs, and lack of technical proficiency of the techs that seem to always provide mixed results. In order to be certain you have a true zero try the following: With your air box assembly and base off, the TPS sensor is right on top of the throttle body. If your TPS has two orange dots, you have the new revision with the vertical alignment tabs. This procedure applies to the old style as well. Adjust both throttle cables so sufficient slack is available. Back off idle adjustment cable until the throttle plate will snap shut without touching the idle cable stop. With a scribe, mark the TPS position by scratching a single line from the throttle body to the TPS. This will serve as a reference point just in case. With a 7mm open end wrench, remove the two TPS mounting bolts and remove the TPS from the throttle body. Clean the debris from the back of the TPS and the side of the throttle body. Apply a small amount of high temp silicone grease to the tabs on the TPS to minimize wear in the future. Replace the TPS but leave the mounting bolts slightly loose and rotate the TPS full left (counterclockwise). Insure the throttle plate is totally closed, then rotate the TPS until you feel the spring make contact with the alignment tabs on the throttle plate. Rotate the TPS slightly clockwise to preload the mechanical zero position and secure mounting bolts. Most of you will notice that according to your reference marks, your new position is just slightly right of the old position. Now your TPS and throttle plate are truly aligned, without play. Connect all wiring and perform a TPS reset, just like the manual states. Now you have a solid TPS zero. Ride and feel the difference. I have no more sneezing or lean like surging. (I have been told that this procedure is in the manual somewhere. I just had to learn the hard way, as usual). | ||
| Paul_in_japan |
Treadmarks- great reply there. I'm not sure how I will go trying to explain that to the mechanic with my limited Japanese but I'll give it a try. I'm gonna drop into the dealer tomorrow to see if he has made any progress. | ||
| Paul_in_japan |
Picked up the bike-Mechanic says now that it was an intake leak. The bike seems to be running much better although a lot hotter!! I pulled into the garage in the dark and noticed the headers glowing orange. Ive never seen that before. I checked badweb and it seems to be quite common. I called the dealer about , he says Its common too. Just wondering why I never noticed it before. anyway Ill ride it and see how it goes. thanks for all the help | ||
| Punkid8888 |
I just wanted to add one thing. before doing any tps reset I recommend cleaning the throttle body with some carb clean on a rag, open the throttle and wipe all the built up coaking around the throttle plate contact points. I had an issue with a sticky throttle and a creeping idle that I continually adjusted for about 2 months. I finally when and cleaned the throttle body, no more sticking throttle and the idle returned to normal. So this build up will give you a false tps reset if not cleaned first. Just my 2cents |
