newbie
New member
so technically with it unplugged it would run like the 98 and 99 cause they did not have a tps and would run only on base spark plug advance on rpm? and if i can get high rpm with it unplugged i would know its the tps?
Sxviper02
New member
newbie i've been reading all your threads about not reaching rpms. I have an 02 sx viper 700 doing the same thing. I'll hold the throttle wide open from a stop and it'll spike to 8600 rpms, then it'll drop to 7000 at 60 mph. then after that nothing else more than 7k. Are you only getting a max of 7000rpms?
I don't think unplugging the TPS helped Bob diagnose his issue which is why he went through the trouble of setting up a degree wheel and make a harness to monitor TPS output. It couldn't hurt to try it but no change in the symptom wouldn't necessarily deem the TPS guiltless. I would think spark advance mapping for each of the three different systems ('98-'99 2D, '00-'01 3D, '02 3D w/DCS) would be quite different especially the default map when one of inputs is missing. Search Side Show Bob TPS
stock can and clean clutches?
newbie
New member
Sxviper02 !! Yes that is what it does. What was your issue???
newbie
New member
I have stock cans and clutches are new springs
mod-it
Member
Is it dropping a cylinder? When you run it WOT for a while, have you tried hitting the kill switch and then reading the plugs?
Another thought is the power valves servo. Only pulling 7k is about the right rpm if the PV's aren't opening. They can fail but not necessarily not move or seem completely dead. I've read that some still move but will have a funny kind of twitching when you drop the rpm's below 900 rpm when wanting to set them to the proper place for adjusting them.
Also could the crank be out of phase?
Could also still be a stator issue. You said everything looked ok and it is low miles...the stator on my 03 viper failed at like 2k miles or thereabouts and there wasn't any sign of a problem visually.
Another thought is the power valves servo. Only pulling 7k is about the right rpm if the PV's aren't opening. They can fail but not necessarily not move or seem completely dead. I've read that some still move but will have a funny kind of twitching when you drop the rpm's below 900 rpm when wanting to set them to the proper place for adjusting them.
Also could the crank be out of phase?
Could also still be a stator issue. You said everything looked ok and it is low miles...the stator on my 03 viper failed at like 2k miles or thereabouts and there wasn't any sign of a problem visually.
so what does the tach do? does it go up above 7000rpm then drop back or what. for people to help you need to be specific in the description of the problem, we cant hear or ride the sled to make observations. After reading thru all this thread, sure sounds like a powervalve issue. One last question does the sleds water temp light blink 3 times on start up? does it blink when wide open and low rpm?
newbie
New member
light blinks twice immediatly on start up and no lights after that. it could b the servo but i took cover off and seemed to work in junction with throttle. sled jumps up over 8k and then drops to just under 7k at wot.
with the servo plastic cover off, start up sled and observe the servo motor as you turn down the idle to under 900 rpm, it should open the valves all the way. does it do this? is the servo wheel jerking the cables as it opens or smooth?
also, if you push on the cables where they go onto the servo wheel, the gap where you can see the braided cable, are they each "spring loaded feeling"??? when you push the cable towards servo motor
also, if you push on the cables where they go onto the servo wheel, the gap where you can see the braided cable, are they each "spring loaded feeling"??? when you push the cable towards servo motor
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newbie
New member
i turned down servo to 900 rpm and it does open. i ordered a used servo for 40 bucks just in case . the lines move freely. will update in a week or 2. i think season is done here anyway, no snow. last 2 years have been horrible
Sxviper02
New member
I cleaned the primary clutch. Although I dont know what color spring it's supposed to have? Everything looked ok. Pulled the carbs off again just make sure nothing built up in the jets. Cleaned the gas tank.
Finally I just pulled ypvs. The valves looked like they've never been cleaned. Carbon built all around and oily sludge on them.
I did just do the 900rpm thing. The servo is fluttering opening and closing to keep the idle going. Spring tension seems good.
Btw it does not have stock can on it. Not sure the make of it. Sled ran good early this year. After about 40 miles it started acting up.
Going to go test it on the lake. No snow around me.
