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If your accelerator pedal feels like there is slack in cable and your throttle response is diminished (and its not just the spring behind the pedal), check your throttle cable and adjust it if necessary.

As always, there is risk involved in working on your car, be careful, do not hurt yourself or your car.

What You'll Need:
10mm socket
(2) 14mm wrenches or crescent wrenches (or combination thereof, I used 2 crescent wrenches)

First you'll need to pop the hood, I didn't take a photo for this since I think you should all be able to figure this step out.

In order to get to the throttle cable, you need to take off the black engine cover with the "L" emblem on it, use a 10mm socket to do this.



Towards the back of the engine, behind the throttle body and intake manifold, you will see the throttle cable coming out of its protective sheath and then connecting to the wheel on the throttle body. The cable should have just a touch of slack in it, you do not want it to be tight and making a throttle input when you are not touching the gas pedal. In order to tighten the cable, use both wrenches on the nuts and loosen the passenger side nut, slide the cable to the driver side and re-tighten, in order to loosen the throttle cable, do the opposite, loosen the driver side nut and slide toward the passenger side.
 

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Back from the dead..

Recently, my gas pedal felt very slow to respond. Checked the throttle cable today and what do I see?... Throttle cable was loose. I can press with ease and it will slack downwards.

I guess this is a normal thing for IS 300 with high mileage? :confused:
 

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Bringing this back one more time, yesterday after a lot of detail work I decided to give my engine a good once over and noticed my throttle cable had a good bit of slack in it. After tightening it up, I let it idle for a good 10 minutes shut it off and forgot about it. This morning I jumped in to head to work, and after about 2 minutes of driving ( half way through warm up) I rolled into the gas and it seemed sluggish to downshift (at roughly 30mph it took somewhere around 50% to downshift to third) and when it got into 4th at about 25-30% it stumbled a little bit (which it's never done). I babied it most of the way from there thinking it had not liked my adjustment. Almost to work I grabbed 3rd and rolled into it, and noticed a sucking noise from the intake (airbox lid off) I've never noticed before, at next 4 way I punched it in second and ran through the top of 3rd, no stumble, noise still present.
So my question, does the ecu reference any other sensor other than the one on the throttle body for throttle inputs? I know some DBW systems have a pedal mounted tps just curious if it was relearning or if my stumble was something in the warm up enrichment I've just never felt before.

Thanks ahead of time
 

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Does the oe computer reference any other sensor other than the one on the throttle body for throttle?
I ask because after a throttle cable adjustment I got a little bit of a hesitation on down shifting, and a slight stumble on my first drive cycle, but by the end of the drive it seemed to have cleared up and for the first time I can hear noise coming from my open airbox at wot, car seems to be running like a top, but smelled like it had been driven pretty hard if you know what I mean.

Maybe im over anylizing, and my sluggishness and stumble was all a result of still being half way through warm up cycle ( was at around 50% throttle). Just didn't know if this car had a second throttle sensor like alot of DBW cars.
 

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I have some slack in my cable and it cant be tightened anymore. think i need to replace the whole cable assembly??
 

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I have some slack in my cable and it cant be tightened anymore. think i need to replace the whole cable assembly??
As in there is no thread left at the mounting bracket? Then yes, you tightened the cable and now it needs replaced. This is because after you tightened it before every time you floored it after the cable would stretch because the pedal would no longer go to the back stop. It is there for a reason and if you tighten the cable much then you need to space out the back pedal stopper or you will stretch the cable. See my pics below

http://my.is/forums/f87/hesitation-throttle-456266/index3.html#post6791218
 
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