Celica Problem

[NooB1FieD]

So, my celica has been running GREAT no problems for the last 5+months. But, I want to know if someone knows what can cause this

http://s49.photobucket.com/albums/f2...16-07_0244.flv

Its really got me boggled, if I give the car 5-10 % throttle, the rpms jump. Anyone know what causes this? It only does it when part throttle, all other rpm/throttle positions are fine. Thanks for any help! I didnt even know about this until I replaced the starter and was idling, and gave it a little gas just after I put it back together, and I held the gas at part throttle, and the rpms jumped up and down exactly like in the video. Im sure it did it before I replaced the starter though.

[RadioZero]

i would suggest checking all your vacuum lines. make sure none are split, cracked or disconnected. you could have bumped something loose during the starter install.

[xXCriticizeXx]

you have a GT-S so your lift system could be malfunctioning. When you got the car did you switch out the bolts for it? It cost like 5 bucks to put new bolts on.

[NooB1FieD]

you have a GT-S so your lift system could be malfunctioning. When you got the car did you switch out the bolts for it? It cost like 5 bucks to put new bolts on.

The Tvis is functioning completely normal. I dont know what bolts you are talking about. Where are they located? The VSV that the tvis uses is a vacum activated switch. Im guessing my vacum lines are whack, because my dad and I were trying to read the schematics but the pictures and diagrams were crappy.

[NooB1FieD]

Messed TPS, sticky IAC, vacuum leak... Do you notice a torque variation while driving?

Yes, so when I am shifting between 1-3k rpm, the engine will buck after the clutch is engaged, as soon as I hit the gas, it feels like a bad motor mount, but one was replaced and the others are fine. I know its not my shifting, been driving too long. so when I have my foot off the gas pedal, the car bucks down while decelerating, and when I apply ANY gas, even a hair, it bucks and jumps back up. I replaced the struts with KYB (kill your back) and It cut alot of the bucking down, but it still does it pretty hard, somthing is going on.
3k+rpm, and the bucking does not occur, and it is particularly hard bucking while in 123 gears, 45 require too much torque and they make the car pretty stable at all rpm. Thanks for the help so far, I am double checking my vac lines. Keep the hints comin!

BTW, the TVIS functions fine, only problem is the mods Ive done have moved the power band around so I get a flat torque curve around 3.8-4.2k rpm. This is somthing I will fix later on, after paint (need a rpm activated switch.)

[TSi+WRX]

Messed TPS, sticky IAC, vacuum leak... Do you notice a torque variation while driving?

^ I thought about the IAC diagnosis, too.

The OP's latest/last post makes me veer even more in that direction.

Still, I'm definitely no mechanic - just a backyard hobbyist wrench. YMMV.

However, the IAC is definitely worth a look, I'd say.

[NooB1FieD]

Im going to my dads shop to check the vac lines, and pull any codes in the ECU.

[Arashi666]

just for reference was this one was a 3S correct.......

[NooB1FieD]

Yes, its a 3S-GE 135hp, 125lb tq. Its a JDM engine though (US one died from piston seals blowby)

[wanderingmind]

My guess is IAC system.