Hey guys, Im sure some of you guys have some input for me because i cant seem to get my head around it....

I noticed that my throttle has become stiff especially when the car is cold,
the stiffness is only at1/8th of the beginning of the throttle position.
The other 2/8th right to wot is smooth.

It's as if it's sticking and thats annoying when you trying to feather the throttle to take off or maouver the car into the garage or traffic etc...with my excedy twin you can imagine...

Alright--- started to investigate and found that it doesent do this when the car is off, only when it's on and when im passing through this 1/8th zone it makes a little zz sound. I opened the bonnet and moved the butterfly valve manually and it makes this sound from in the compartment but from where...? Obviously there is a restriction or some kind of sensor engages when the cars on again creating that minor restriction....

Any input would be appreaciated...

dxbtune

 

I had the same problem with my 8. Never now with the 9. Only when it was real cold like freezing temps. After warming up a little throttle was fine. Didn't hear any noises though like you.

 

bump

 

Did you try checking at the throttle body itself? See if it is smooth from the throttle body. After that you could eliminate the throttle body or cable.

 

^
yup checked that... its not the cable or throttlebody since it doesent happen when the car is off.. weird....

 

I had a similar problem with a Mustang I owned. I just had to clean the TB all around the butterfly valve with TB cleaner and the problem was solved. A cheap, easy fix and even if it doesn't work you haven't lost much.

 

Another possibility to check out is the TPS, it could have a worn spot.

 

^ i have a feeling its related to that...
will let you guys know for future reference...

 

try cleaning the tb n see if it helps. when its been sitting and cooled it might be sticking a little. after it warms up it might work it self out into motion. good luck

 

Occassionaly my throttle will stick at the closed position. It is like some little projection under the dash is catching the edge of my shoe. If I push harder then there is what feels like something snapping and then the throttle is free.

Looking under the dash I find nothing that my shoe could catch on. One of these days when I am bored I'l clean the butterfly and the problem will be gone.

 

Thats exactly what mine is like... i tried to go a little more into detail though, good example...



Guys i was thinking...
If i were to adjust my throttle screw so that i'm reving around 2k rpm then go into my map and drop it down a little towards 900rpm idle, I really think that would solve the problem..
after i got my cams installed my idle was out of whack and i played with the screw and the idle on the map to get it just right.. perhaps i adjusted it too much in one direction where perhaps the butterfly is going past the close position and opening a little in the oposite direction allowing it to idle... or its mechanically impossible..?
Another weird observation is that there is slack on the cable leading to the trottle body and the car is idling would that indicate anything to anyone....
by the way on my datalogs when the car is wot is shows 100% on the tps so i know it not that loose...

just throwing thoughts in the air will get to the bottom of it....

 

Check to see if it does it when the car is not switched on... mine only does it when the car is on which indicates theres some kind of mechanical solenoid system thats doing this.. perhaps the idle stepper or something.. dunno

 

alright like what copro said get some carb/throttle body cleaner. ITs possible the carbon build up is cuasing it to stick. It happened to my 90 talon tsiawd. Just remember when it says "spray it through your intake" you cant do that for obvious reaons....your turbo is gonna love it lol. well what i did was disconecnt the upper ic pipe then unbolt the TB close off the manifold inlet and the upper pipe then spray that bish and wipe it clean. remember to do both sides. GL

 

i dont know about adjusting the throttle screw to 2k. thats a little high. maybe to like 1200 or so but not quite that high

 

Maybe manifold vacuum is pulling the throttle plate into whatever varnish buildup there is in the throttle body. There isn't anything else connected to the throttle but the the cable and your foot. The stepper motor could maybe lose a coil and be vibrating. But all it does is uncover a hole that bypasses around the throttle. There is no physical connection other than that they are both located in the throttle body.