Throttle Position Sensor- NEED HELP!

[yam429]

Has anyone figured out what is causing this problem?

 

[74Nitro]

Are you sure there is any thing really wrong here....?

 

[yam429]

My brothers supercharged Phazer is doing the same thing. We bypassed the Gem controllers and still can't get within the WOT range of 100. Best we can get is 48. It stumbles & hesitates bad on low end at about 1/4 throttle. We've replaced TPS with same results.

 

[Anjill]

Bad grounds?

 

[4strokes]

Are you sure there is any thing really wrong here....?

I second. all the posts I ever read here for years are usually people chasing ghosts. If I recall, reading years ago, the sensor reading is percentage of voltage, not throttle opening. meaning that 100 % throttle opening doesn't mean 100% sensor voltage. Also remember reading that the oem specs are not what people were coming up with oem untouched. Mine is oem tune etc. with 24000 miles and I have never even seen the sensor, also bypassed tors when new. any popping I ever had at all was donut time. Isn't popping after a tune a tune issue? Also don't forget about burned valves etc. Just reshimmed mine and the exhaust were all 1/2 what the should be.

 

[yam429]

We tried bypassing TORS & that made no difference. This thing doesn't just pop here & there, it runs horrible as if TORS is activated once you get past quarter throttle it runs alright it is just low end that we are having the problem.

 

[yam429]

We are checking all connections and grounds today.

 

[4strokes]

We tried bypassing TORS & that made no difference. This thing doesn't just pop here & there, it runs horrible as if TORS is activated once you get past quarter throttle it runs alright it is just low end that we are having the problem.

I'm not surprised it didn't help, running horribly wouldn't have anything to do with it.

 

[4strokes]

My brothers supercharged Phazer is doing the same thing. We bypassed the Gem controllers and still can't get within the WOT range of 100. Best we can get is 48. It stumbles & hesitates bad on low end at about 1/4 throttle. We've replaced TPS with same results.

good old fashioned source voltage and output voltage right at the sensor would tell more

 

[74Nitro]

I didn't know it was possible to bypass TORS. How are you doing this?

 

[Anjill]

https://ty4stroke.com/threads/tors-bypass.125342/

search the site, plenty of info

 

[4strokes]

super simple. take throttle lever pin out, stuff a cut to length nail or roll pin etc next to it and reinstall, leaving throttle positive pinned pivot position and pushing the switch internally at the same time. gives a more solid action too. If the throttle sticks and you're not smart enough to shut it off or bail, Darwin will step in.... But I believe in these modern machines, when activated, it just retards timing over idle speed and gives a code. old cats etc in 80s and 90s would act up, trying to kill ignition intermittently...

 

[R00STER]

This might help with your TPS questions.

 

[74Nitro]

super simple. take throttle lever pin out, stuff a cut to length nail or roll pin etc next to it and reinstall, leaving throttle positive pinned pivot position and pushing the switch internally at the same time. gives a more solid action too. If the throttle sticks and you're not smart enough to shut it off or bail, Darwin will step in.... But I believe in these modern machines, when activated, it just retards timing over idle speed and gives a code. old cats etc in 80s and 90s would act up, trying to kill ignition intermittently...

Ok, makes sense, but a multimeter test of the switch would confirm if the contacts were sending weak signal, or even the diagnostics on/off throttle switch feature. I'm not sure why anyone would want to bypass this aside from testing.

 

[4strokes]

a couple of multimeter test is not proof that its working correctly and the older snowmobiles were plagued by worn throttle bushings, icing, etc.. I like the throttle feel of solid and I have also noticed it make an older cfi switchback easier to brake trail, because it kept the engine from braking and diving, allowing it to rev down naturally. same deal with the little 50 and 90 atvs. I will tell you first hand tors is no garauntee it will shut down, my apex had a butterfly hanging up at just above an idle, when new. rode it like that, nearly getting killed a bunch of times crossing mud holes etc...tors did nothing.... dealer said, never heard of it.. fixed the throttle body issue myself and disconnected tors many times since. Not sure why guys trying to run dangerous 200-300 hp machines are so hung up on throttle safety. for sure to be the least of the days problems...