ok so i have checked the wiring diagram and it checks out. ive replaced the ECU with no change, and ive replaced the TPS with no change (still wont run). anyone have nay advice on what to do now? i would like to check the calibration on the TPS but im not sure how.. im still getting crazy voltages on all three wire like i was before.. see above.

 

Start with the basics; how much compression doe it have, does it have spark, is the spark at the right time - if that checks out all that is left is fuel and air. What do you have and what don't you have?

There is a place called a dealership where they have the electronic equipment to check and set the calibrations.

 

it was running when i bought it but very rough.. would pulse-idle only and die with throttle. i replaced the TPS and hasnt run since- i know the spec on the TPS is 0.65v at idle but im not sure how to check that. so i know i have spark, i know i have fuel and air and compression, however i will double check those, thanks for the reminder! so the big question is can i check the TPS and calibrate it myself without having to throw the bigtime $$$ at a dealership to look at it? (bigtime meaning i dont want to put much more then a couple hundred back into this machine)

 

I haven't had any luck using dime store multi-meters to set voltages and you need to make up a wire tap lead to check the voltages with everything connected and running. Even my $900 Simpson has difficulty getting accurate readings. The best way is connected to a computer to read voltages in real time with the engine running an the voltage can be adjusted both physically and digitally.

 

gotcha thanks.

 

alright, so i took the machine to my local dealer and they said the wiring harness needed to be replaced (its cut and reconnected at the tps and one other place) they quated 1000 to begin with that and said they didnt know what else theyd find after that. i asked if they could just set the tps and they agreed after some haggling, so i paid them for one hour of labor and they told me the tps was bad. they said they could get another throttle body with the tps on it for it but it would be $500 just for the part. i have since swapped the ecu to my other 850 and it ran perfect so i know for sure it isnt that. i checked the wiring again and all checks out so ig i got a bad tps. gonna order another one but still not sure how i could set it myself. pretty sure the dealer wouldnt want to fool with this bike agian as they almost turned me down last time and id rather not pay them another $100 to hear "tps is bad" again

 

So to my knowleadge you need the diag equipment to set the TPS to the ECU. So there is something to it!!

 

Calibrating the TPS is near impossible without special tools and is a very tedious and complicated process even with them. Pretty simple with the Polaris Digital Wrench software though.
It being a 2013 with the symptoms you describe, one of the very FIRST things I would've checked after going through the easy and simple stuff is compression, timing and check to see if the cam chain gear on the crank had slipped (in that order). The crank gear slipping is not an uncommon occurrence on the pre-14 850's with low miles that "seem" to have electrical running problems... rough idle, won't take throttle, backfire, etc. You also said the machine is otherwise "rough" but has a "new" crankcase. That also sounds (to me) like a clue to look in that direction... But I'm a skeptic lol.
If all the wiring is jacked up and the TPS was changed without calibration and other electrical components changed around its anybody's guess now though. That's why the dealer don't want to mess with it unless you're ready to spend big bucks for THEM to throw parts at it lol. Sounds like they don't really have a clue either but if you want to pay, they're ready play.
Unless you're ready to spend whatever it takes and start with the basics from the engine out to do whatever it takes, you may be well advised to part that machine out and try to recoup as much your $ as you can.
Good luck

 

alright thanks for the input guys. i know im a tight wad with this stuff so thanks for putting up with my bs also. you said setting the tps is near impossible? thats what im wondering is how (if i can) can i set the TPS without digital wrench. if its tools i need ill buy them, im tryna be tight with this machine, not tools that ill use agian in the future. and i will check the compression and timing gear. will also let yall know all the codes its giving me next time im working on it. if parting out is what it comes to im not opposed to that either, just wanted to give it my best shot first

 

You can probably just back probe the connector, loosen the TPS screw and with the ignition on set the base voltage to 0.71
I don't have specs for your machine but that should get you in the ballpark.

 

okay thats what i was looking for, which wire for ground and which for pos should i be testing? and i assume i can judge from the color of the plugs which way i need to micro adjust it from there to get it burning right?

 

Let me know how checking the plugs goes - you have to run it for about 5 to 15 minutes at the speed you want to check it at and then kill the engine without changing the throttle setting and coast to a stop without the engine being turned by the wheels (clutch disengaged) - better yet to put it on a dyno and check the fuel to air ratio electronically. No lead fuel and alcohol means the plugs should come out white with a slight grey to light black on the ground electrode.

 

Spun Timing Gear

 

yea ill have to check that too, i wouldnt doubt it.

 

Yep....2013 850

 

ok so i finally got back around to working on this bike. compression on one cylinder is almost 180psi and 140psi on the other. is there a way to check timing without pulling the stator cover?

 

Depends on which timing you want to check - if it's cam timing, you can use a straw in a spark plug hole to find TDC of the piston and then the marks on the cam gear - if they are off, then the engine cover has to be pulled for any further diagnosis.

If you are checking flywheel timing (to the best of my knowledge) you have to pull the cover, again use a straw to find TDC of the piston and inspect the marks on the flywheel and engine.

If the cam timing is off, it can be corrected a few different ways, but they all involve pulling the flywheel and welding the drive sprocket to the crankshaft.

 

alright sounds like a plan. which of the pistons should be at tdc to check time, mag or pto? And say the timing gear on the crankshaft is twisted can i correct and weld it with the crankshaft still in the bike or will i have to pull the motor and disassemble the bottom end to get to it?

 

so i found that the mag piston is supposted to be at tdc when checking timing so timing checks out on it, the two marks on the cam sprocket are in line with the ledge of the head when the mag piston is at tdc (using a skinny long bolt into the spark plug hole to check the piston. so unless its just timed on the wrong stroke it would have to be the TPS right?

 

If the spark was timed on the wrong cylinder, just swapping the plug leads would get it to run

 

oh alright ill also try that. but if it was reversed wouldnt it not run period?

 

Yes - I was under the impression it would not start

 

it wont but thats because i ruined the TPS i bought for it. it was pulse-running when i bought it. it quit running when i messed with the TPS

 

Have you checked fuel pressure?

 

i have not yet. ordered a new TPS and was about to take it back to the dealer to have them set it for me and get that settled. thats the main thing thats holding me up so far. i think i ruined the last one that i put on it by installing it incorrectly (installed with throttle closed and had to twist it to get it lined up)

 

Alright got another question. Getting two more codes that the service manual says are related to the injectors. Seems like it’s not getting any fuel. I hooked the new tps up to it properly this time following the instructions in the service manual and it cranks but won’t fire. So what should I check in regard to the injectors? Still getting the stuck throttle code not sure why.

 

These are the two injector codes I’m getting