2007 TRX 450er NO SPARK! problem help!

[irace450]

Im trying to figure out a problem for my brothers quad, i live hours away from him so its hard to tell. just looking for some input on what someone else might think the problem is.

Ok, so here it goes. He has a 2007 trx450er, he was having some carb issues after installing a new exhaust, so he took the carb out and re-jetted the carb with the provided jets that came with the exhaust. he said he put it together and rode it and i still needed some carb work, he told me that after he rode it he decided to change the throttle cable because his was starting to frey, after changing the cable he said it would not start and said that when he pulled the plug and checked the spark there was no spark. After doing some reading my thinking is the CTPS (closed throttle position sensor). This may not be true, but i read that the CTPS can ground out the ignition if some things are not set right on the carb? like cable free play. but i do not know how that works so thats why im asking for help.

If that is true then how do i go about reseting it? I do not have a service manual for that bike and have never messed with the tps so please help if you can!! if its not that im thinking it could be a stator issue. but its hard to believe changing a throttle cable and ending up with no spark could be stator related.

I had him check his connections as well, he said all connections were well connected.

[DnB_racing]

just take the 2 wires to the throttle switch and jump them together. that switch is only trouble bypass it...

its definatly what your problem is

[trx400Rider]

Im having the same issue , recently I have re jetted the carb and change the throttle cable to a +2 cable and A few days after I installed it, it wouldnt start. I have gone through everything and read this post about the TPS. I connected the tps wires together and it didnt seem to help. but I removed the button from the thumb throttle , and if I repeatedly push the button like 20 times it fires up. thats werid to me. what can it be? cause it seems like that irace450 and I are having the same issue with this TPS crap =/

[irace450]

Thanks DnB for the input, i cant mess with it till i get home tomoro so ill give that a try and see if thats the problem. how and where should i jump the wires together?? at the connector from the ICM? or am i supposed to cut the wires and hook them together?

And i couldnt see how the tps being the problem if your able to start it by pushing the start button a bunch of times, sounds more like a switch problem, but the only way to back that thought is to test the switch. You might check your connections and make sure theres no dirty or loose connections. you want to isolate your problem by testing from the coil back till you lose power. the coils power is wired to the ICM so if your getting power there then it could be an electric switch (like my problem). if you are getting a good spark then its a mechanical problem.

[DnB_racing]

Originally posted by irace450
Thanks DnB for the input, i cant mess with it till i get home tomoro so ill give that a try and see if thats the problem. how and where should i jump the wires together?? at the connector from the ICM? or am i supposed to cut the wires and hook them together?

actually the way I usually do it is...

I kill 2 birds with one stone, meaning I do the green wire mod and tors bypass at the same time.. both systems are from the same connector on the cdi
looking front to back standing in front, the first connector on the right of the cdi

the green wire mod is... you cut the green wires at the cdi and isolate both ends..

and the carb safty actally needs one of the 2 safty switches (throttle or carb) to go to ground

i take the cut green from harness side from green wire mod, and take one of the tors wires I use the grey/red stripe wire, and cut it from the harness and tie it to the green

[irace450]

Ok so what is the green wire mod for? like whats it do cuz ive never heard of it till now. j/w and the TORS what is that? i think i know what to do im j/w on what each of these things do

[irace450]

basically what im gettn from this is cut the green wire from that connector and the grey/red wire from it. then splice the grey/red from the ICM side to the green from the harness side. but then what do i do with the other cut wires? like the other cut grey/red and the other cut green that are not hooked to anything? do i just tape them up or what??

[DnB_racing]

tape or heat shrink.... basically isolate the tag end

the green wire mod releases the rev limit
so you wont notice any real difference unless you have a high output motor, but its just another limit imposed by the California tree huggers

sorry.... (tors) throttle override system.....carb safety,or close throttle detection

[irace450]

alright man, and the TORS bypass is what the tps fix is??

[DnB_racing]

Originally posted by irace450
alright man, and the TORS bypass is what the tps fix is?? tors and tps are 2 different things

tps is mostly used in aftermarket cdi, and is absolutely needed for FI

tps is throttle position system, used in programmable ignitions to change timing, but the stock cdi isn't adjustable, and the tps does very little if anything on your stock ignition

tors or carb safety is used for for loose cable indication, if your throttle cable is too loose it wont allow the quad to run, and is a problem just waiting to happen, another useless idea forced upon us by previous lawsuits

[irace450]

ah ok ok thanks for clearing that up! haha