TPS not responding on ECMspy

[Thunderhead]

Hello there! Long time lurker, 1st time poster. So I did A LOT of searching before posting. Good lord this place is a gold mine.
Bike is an 07 XB9. Just replaced rocker cover gaskets, buttoned everything back up then it ran terribly under load. Idle was ok but when rev until you got about 30% or more onto the throttle -> sputtering/no power. Checked all connections, didn't miss anything, everything looks great, no tears, pinches, etc. It ran great prior to gaskets. Attempted to do TPS reset per the many many posts. The TPS does not respond AT ALL when you snap the throttle to ensure function (what should be the blue bar percentage indicator on the overview page). I unplugged at it shows about 13% plus an error code (duh). Plugged back in still unresponsive.

What am I missing or what have I done wrong?
Bonues: Oh yay, fun times - since it's an 07 I can't do the Mustang TPS replacement per these forums. Yar.

Thanks ahead of time!

 

[34nineteen]

OK, a few questions....

How are you connecting to the ECM wired or Bluetooth (Buelltooth)?

Also, what program are you using to connect to the bike? ECM Spy, ECM Droid, etc?

What error code are you getting?


I had a problem along the same lines a few years ago....

What was happening was that the bluetooth module would lose connection to the the bike (esp when warm/hot - ambient). At that point the TPS reading wouldnt register, nor would anything else. The program (ECM Droid) would move through the different screens and act like it was still connected (when it wasnt anymore). I realized an easy way to verify it was connected was to have it turn the fan on. Wen it wouldn't, then I realized the bluetooth connector (not Buelltooth brand) was wonky. If I disconnected and tried to reconnect, then I would get an error as it went through the "pages" while connecting, and wouldn't reconnect.

TL;DR... make sure that you are still actively connected to the bike.


and welcome to the board.

 

[Thunderhead]

HAHA!!! After a bunch or failures, I tried running ECMspy (wired) as an administrator. Not much better. Had some privileges but def not all. Then I hit all the buttons (not really) and toggled between online/offline modes. That was it! Then I got the TPS 'blue bar' that actually changed values, set to zero, Reset TPS, dailed back to 5.1 then set idle. Taa dee f'n daa. Only idled/revved so far but it acts the way it should. Man, these TPS things are real temperamental huh?

Thanks dudes, I'm sure I'll be picking your brains again...hopefully not soon.

 

[Thunderhead]

annnnnddddd...that didn't fix it. So when I reset everything I only had it mostly buttoned up. That was without air filter and other assembly. Since I've correctly reset TPS and set idle - it's back to the dying/no response after roughly 30% or more of throttle input. I've gently revved it to about 3K RPMs then attempted to rev it beyond the 30% threshold and it just wants to die and not respond at all. I have since zeroed, reset TPS, and brought it back up to 5.1% +/- since reinstalling the filter and everything. No change. No troubleshooting codes either. Do I have to mess with AFV or something? This is really frustrating.

 

[Chicknstripn]

Check that the velocity stack is seated properly. It’s the round rubber tube that connects your throttle body to the air box base.
Sounds like it’s not seated all the way down on your throttle body and therefore choking the engine out when above 30% throttle.

 

[Cooter]

No offense Thunderhead, but it really seems like you aren't well versed in ECMSpy. I would suggest stopping the guesswork and "hitting all the buttons" before it becomes a much bigger problem. Replacing rocker box gaskets would never change the tune inside the ECM:upset:

It doesn't sound like the TPS is temperamental, It seems like your connection to the program is temperamental like 34:19 suggested. Connect and set down the laptop on something. With the bike off, get your static TPS reading, and slowly increase throttle to maximum, and back. If the sweep reading is good, move on to the next diagnostic step and quit messing with it.

The bike (and the whole airbox) needs to be completely assembled to run correctly. Running it without the airbox won't fare well. It also doesn't sound like you are riding it. Are you just trying to rev past 3K in neutral, in the garage?

 

[Thunderhead]

Yes checked the velocity stack - good seal. As far as ECMSpy - def not well versed. First time using it honestly. I have spent HOURS reading tons of other posts attempting to troubleshoot this & how to use ECMspy. I didn't really hit all the buttons but the online/offline was by happy accident. Since that discovery I have checked and double checked to ensure my connection because, yes it does stop communicating whenever I'd reset TPS (which I've tried 3 times now).
I know it seems dumb to say it ran fine without the airbox but I just tried it cuz I had taken it on and off like 5 times at that point, so why not give it a shot.
Last, yes this is just neutral in the garage so to speak. I have not ridden it cuz it straight up doesn't feel safe not being able to use more than 10-20% throttle (I live in the city) without the bogging and near stalling.
Thanks guys.

 

[lowkey]

Rocker box gaskets replaced, I'm assuming you rotated the engine? Won't rev does weird things 3K above? Pull the front belt pulley cover off and have a look at the sensor wire to harness connections, specifically the CPS 3 wire plug. Inspect for wire/melted plug damage. Unfortunately this hall sensor is hard to diagnose when not completely failed but when on its way out it will show running issues with heat.

 

[Chicknstripn]

Your plugs are probably fouled out.
Buells do not like sitting static and having the engine revved. Especially when the engine is cold.

If your connection keeps timing out you might want to invest in a more reliable method of resetting you TPS. It sure can’t be good to start the process only to have your laptop disconnect mid reset. Who knows where the TPS has been set if that’s what’s happening.
Also, you can still read what the TPS is going without the bike running as long as you have a good connection. The bike doesn’t need to be running for that. However, I highly suggest after the reset(if you can get everything to work) that you fine tune your idle after taking a ride. Never go by the value in the manual or that has been posted anywhere. Every bike is different. I usually take an Allen wrench( I believe it’s a 1/4 that fits the idle adjustment knob) with me in a ride after a TPS reset and fine tune the idle after the bike had been ridden and the engine is good and hot.
Another thing I’d like to mention, from personal experience, I had a TPS go bad after an engine rotation. Seems extremely random, and I couldn’t figure out what was causing my bike not to start. However, once I hooked up to ECMspy and saw that I had No TPS value, I knew that was my problem. In my case the bike wouldn’t start AT ALL because it wasn’t getting a TPS signal.
Have you checked EVERY other possibility?
Are you sure everything is hooked up correctly?
Are your throttle cables routed correctly?
Without the bike running can you see the throttle butterfly open and close normally?
Did you accidentally switch up the connections for the front fuel inject and the rear?

I’m grabbing at straws here.
I’m sorry I can’t be of much more help.

 

[Thunderhead]

Yes I rotated engine. Checked all plugs/wiring near the pulley, they all looked great. Unplugged them all to inspect for corrosion & such. Looks great.
Double checked fuel injectors. The green wire one is going the the rear, which is correct, accord to this site/other posts.
Also observed AFV at idle and it was 100 once and 99.5 once. That seems good.
I connected first thing today and TPS was still at 5.1. It is being detected and giving out a signal, so the original title of this thread is no longer accurate. Zeroed it out, slowly pulled throttle, it went from 0 to 100 perfectly. Reset and put it back to 5.1
Never messed with the throttle cables.
Butterfly opens and closes beautifully.

Only new info: it and I smells like gas pretty bad. Like there's too much or it's not burning it. There are no leaks to be found.
Going to check plugs now (they were brand new less than 500 miles/3 months ago.)

 

[Thunderhead]

Wow. Yeah that is a very black spark plug, not the oily kind and this thing is virtually new. Dr. Internet says 'overly rich fuel mixture'. My manly gasoline musk will also tell you that.
Not mine but looks like this

 

[lowkey]

NGK DCPR9EIX plugs are what you want. It's an air-cooled motor and starting cold has to overcome wall wetting on the intake manifold/head, AFR's are about 12.0-1 with the cold start enrichment table on a 70-80 degree day from what I've seen. Once the engine comes up to 160C the additional enrichment fueling stops and idle should be 14.7-1 AFR as you would expect to see.

 

[Thunderhead]

Got the new plugs gapped & installed today. Used the same plugs and gap specs previously as well.
Tried to ride it to get a proper warm up/test ride and the more than 20% throttle problem is still there. I tried riding it for 20+ minutes but it just straight up dies once you exceed that 20% threshold. It doesn't even bog down, it just completely dies. It'll start back up but I just keep repeating the cycle, even though I'm trying super hard not to exceed that 20%. It's runs "fine" below that magic limit. I'm at a loss. Very frustrating.

 

[lowkey]

How much is the buy in on this one?:black_eyed: I've got $5 on CPS.

 

[Chicknstripn]

I’m still thinking the velocity stack isn’t seated all the way down on the throttle body.

Just for the hell of it. Remove the velocity stack and see if drivability changes.

You’ve tried everything else about 100 times why not try this once?

 

[Cooter]

Oh man, CPS is a good one lowkey, but I'm in $2 for secondary ignition (fouled plugs/damaged coil). There's no decent info here to work off (still) but guessing is fun and being lucky feels great!:eagerness:

 

[Thunderhead]

As far as the velocity stack - you mean remove just the rubber and reinstall everything else? Or just run it with no stack/filter/box?
CPS = cam or crank position sensor??
I'll look up past posts about the CPS but is there any checking it (resistance I'm guessing) or is it one those sensors that just gives up the ghost randomly?
As your bookie, I got $5 on CPS, $5 on the stack, $2 on ignition stuff. So far this is a pretty good hourly rate I'm paying for. :up:

 

[Chicknstripn]

Just remove the rubber stack, reinstall everything and see if you can accomplish a ride using more than 20% throttle.

Yes- CPS: Cam/Crank(whatever you want to call it) Position Sensor. It's located behind the timing cover. Remove timing cover and visually inspect the CPS. If the glue/epoxy, whatever the crap is, that holds the sensor together is melted or delaminated in anyway, you found your problem. If it looks perfectly fine visually then one way that others have tested it is by heating it up with a hair dryer while the bike is idling. If the idle starts to fluctuate drastically then your discovered your issue.

Good luck

BTW what year did you say your bike was?
And p!ease include model, miles and modifications. Just to get everyone on the same page.

 

[lowkey]

I presume you have a smartphone? Make a video of the bike running and replicate the problem. With TB/stack exposed can you see anything abnormal while it's running? We have nothing to go on so the best you are going to get is guesses here.

Yes heat the exposed sensor (nose cone cover off) heat gun or hair dryer, should start running worse as it gets warm if it is failing. It is a hall sensor and there are two notches on a cylinder behind it which trigger top of piston stroke for each cylinder. Your sensor isn't completely dead yet as the bike will start, can't test with volt meter in this state.

Velocity stack seated properly should be as simple as running your finger down and feeling that the rubber meets the TB without any gap. Outer lip on the stack must also be seated on the air box base plate. Don't forget to plug AIT sensor into it before installation.

 

[Thunderhead]

OK, so removed ONLY the stack and it runs great. How the hell is a rubber seal related to detecting potential CPS failure? That sensor is down on the engine casing not way up top. It was really strange to be able to actually ride and punch it a few times.

Oh yeah bike is 07 XB9 Lightning, previous owner put on a K&N air filter on. That's it. I'm the 3rd owner. It did come with the ECM wire so who knows if he messed with EEPROMS/fuel maps/etc. Like I said earlier, it had just fine since I bought it in August. Appreciate the the input!!