I have a 2005 polaris sportsman 700 efi,the only mods are a k&n air filter,the atv is well maintained by myself(i am a master automotive tech),the problem i am having is this,today i was towing a trailer that weighs about 400lbs.in high range going about 20mph and opening the throttle wide open the atv will bog down,i have also noticed this problem when just driving down the road and the opening the throttle wide open it will bog down.haven't diag.the problem yet,could possibly be tps ,wiring or fuel supply problem,fuel filter was changed last year and was clean,atv has 250 hrs on it.does anyone have any quick ideas ? thanks

 

If its not throwing any codes,the usual problems we have are the t-bap sensor connection on the EFI models. kit # 2875542 for harness kit. Towing loads in HI range doesnt help matters either! Might want to check the belt for glazing??

 

the part number you gave for the t-bap harness kit,is this a polaris number? checked for codes and none were found,fuel presure is about 42 psi running.have not checked the belt yet,i will be replacing the belt soon.i did remove the harness conector to the t-bap sensor and it looked wet,possibly from cleaning.

 

This is the Polaris part #. Usually the wires will pinch or fray internally on the harness or on connector itself.. The kit has a new connector along with about 8" of wire,solder connectors and plastic sheath.
Try drying out the harness and see if helps.