Throttle Cable Adjustment?
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From: Jacksonville Fl
Throttle Cable Adjustment?
I’ve been digging through the archives and I see several people talking about when the gas pedal is at WOT there is still play in the cable but no one really answered the question of “is the throttle body suppose to open fully when the pedal is all the way to the floor”. I was just under the floorboard putting some lubricant on the clutch mechanism and saw mine is the same. When at wide open, the throttle body still had about 3/4 inches of cable travel left. The manuals don’t say all that much about max travel, just to check full throttle operation. Under the pedal is a threaded shaft with a lock nut on it. Mine was screwed all the way in giving the least amount of travel. I adjusted it so now when I go WOT, the throttle body is opened fully. Should the throttle body not open fully? Maybe only open till the full throttle micro switch is activated? Seems like you would want the throttle fully open when you hit the go fast pedal. I bet others out there are not getting full WOT as well. Mark
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From: Virginia Beach, Va.
Mark, if your adjuster is in fact screwed all the way in, the one under the floorboards and attached to the end of the cable...then you in fact have MAX adjustment there.
You have another quick adjustment point, it is under the car, where the cable goes through the body, there is a black plastic adjuster that you would have to back out to tighten up the cable jacket in regards to the cable...this will open up your throttle body more under WOT.
You do NOT want to extend your butterfly all the way, there is a point where it actually keeps rotating around, just a bit, unless there's an external adjustment limiter on the throttle body itself...I don't remember seeing one.
If you like, just take part of the slack out, don't attempt to get all of it out and you'll be okay.
Let us know what you find.
You have another quick adjustment point, it is under the car, where the cable goes through the body, there is a black plastic adjuster that you would have to back out to tighten up the cable jacket in regards to the cable...this will open up your throttle body more under WOT.
You do NOT want to extend your butterfly all the way, there is a point where it actually keeps rotating around, just a bit, unless there's an external adjustment limiter on the throttle body itself...I don't remember seeing one.
If you like, just take part of the slack out, don't attempt to get all of it out and you'll be okay.
Let us know what you find.
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From: Jacksonville Fl
Jeff,
I was able to make the adjustment at the pedal. When the threaded shaft is screwed all the way in, it’s at the minimum setting. I just screwed it out about a ½ inch and now when the pedal is to the floor the throttle body is all the way open. I guess just the vibration over the years worked it loose. Mark
I was able to make the adjustment at the pedal. When the threaded shaft is screwed all the way in, it’s at the minimum setting. I just screwed it out about a ½ inch and now when the pedal is to the floor the throttle body is all the way open. I guess just the vibration over the years worked it loose. Mark
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From: Virginia Beach, Va.
Okay...at first I thought, "HUH??" 
...then I figured out WHERE you made your adjustment! <img src="graemlins/c.gif" border="0" alt="[ouch]" />
I thought you were adjusting the ball and lock nut at the very end of the cable where it attaches to the accelerator pedal linkage.
I now picture that you actually adjusted the part of the linkage where the ball end snaps into the rear of the plastic accelerator pedal itself??
If so, that'll work as well...but will affect the height of your accelerator pedal...so the pedal position may feel a bit different for a few drives.
...then I figured out WHERE you made your adjustment! <img src="graemlins/c.gif" border="0" alt="[ouch]" />
I thought you were adjusting the ball and lock nut at the very end of the cable where it attaches to the accelerator pedal linkage.
I now picture that you actually adjusted the part of the linkage where the ball end snaps into the rear of the plastic accelerator pedal itself??
If so, that'll work as well...but will affect the height of your accelerator pedal...so the pedal position may feel a bit different for a few drives.
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From: Road America
Originally Posted by Jeff Curtis
You have another quick adjustment point, it is under the car, where the cable goes through the body, there is a black plastic adjuster that you would have to back out to tighten up the cable jacket in regards to the cable...this will open up your throttle body more under WOT.
Btw-I'm pretty new to the 964, but the chip seems to have made a fast car a bit faster. Unfortunately I don't have any quantifiable statistics to back up the feeling.
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From: Columbus OH
Originally Posted by Jeff Curtis
You do NOT want to extend your butterfly all the way, there is a point where it actually keeps rotating around, just a bit, unless there's an external adjustment limiter on the throttle body itself...I don't remember seeing one.
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From: Columbus OH
Originally Posted by Hildy911
Can anyone elaborate as to where exactly this is? I installed a Steve Wong chip today. At the conclusion of the instruction booklet he suggests that about 1/3rd of 911s have improperly adjusted throttle cables. I had my daughter hold the accelerator pedal down while I checked the mechanism that opens the butterfly. With the pedal fully depressed I could rotate the mechanism another 10 degrees or so. When I did that my daughter noted that the pedal went down farther. When the pedal is released the cable seems a bit limp, so I'm guessing an adjustment is in order.
Btw-I'm pretty new to the 964, but the chip seems to have made a fast car a bit faster. Unfortunately I don't have any quantifiable statistics to back up the feeling.
Btw-I'm pretty new to the 964, but the chip seems to have made a fast car a bit faster. Unfortunately I don't have any quantifiable statistics to back up the feeling.
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From: Road America
Chad-I saw that in your excellent write up on adjusting the pedals. Very slick. While I'm not adverse to making the adjustment at the pedal, as I undserstand it, there's another adjustment underneath by the motor.
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From: USVI
Originally Posted by Hildy911
While I'm not adverse to making the adjustment at the pedal, as I undserstand it, there's another adjustment underneath by the motor.
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From: Cape Town, RSA & Sarasota FL
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From: Cape Town, RSA & Sarasota FL
ahem .... so Adrian's book shows you do need to remove the tray to get to this.
My question now - can't find any pics in the book - is about the manner in which the acc cable should be attached to the throttle mechanism.
Mine has a black plastic connector that holds the end of the cable (clips in around the ball clamp at the end of the cable),
but what is puzzling me is that there seems to be a loose metal clip/nut floating between that connection and the rubber boot that the cable comes through.
Shdn't be floating surely - anyone know where it comes from or how it shd be positioned?
Is it supposed to be clamped over the end of the boot to stop it getting dirty/moving, or is it just right and acting as a little spacer/weight for the boot?
Seems to have the same shape as the boot end. And if it shd be clamped over the boot end, where shd the boot be in relation to the end of the throttle cable?
see this vid re what I'm talking about ...
thanks in advance as ever to all 64Jedi
My question now - can't find any pics in the book - is about the manner in which the acc cable should be attached to the throttle mechanism.
Mine has a black plastic connector that holds the end of the cable (clips in around the ball clamp at the end of the cable),
but what is puzzling me is that there seems to be a loose metal clip/nut floating between that connection and the rubber boot that the cable comes through.
Shdn't be floating surely - anyone know where it comes from or how it shd be positioned?
Is it supposed to be clamped over the end of the boot to stop it getting dirty/moving, or is it just right and acting as a little spacer/weight for the boot?
Seems to have the same shape as the boot end. And if it shd be clamped over the boot end, where shd the boot be in relation to the end of the throttle cable?
see this vid re what I'm talking about ...
thanks in advance as ever to all 64Jedi
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From: Cape Town, RSA & Sarasota FL
So I adjusted the accel pedal nut located (as above - thanks) under the car.
Two benefits
1. pedal is taught (no more slop/play) and more sensitive and car feels like its alsmot supercharged at 4k now!
2. H&T (which was a bit hit and miss before) is now perfect ie pedal is firmer and further out and this easier to blip
also I decide the little nut like piece in my vid above was supposed to clamp onto the end of the rubber boot .. so that where it is now
Two benefits
1. pedal is taught (no more slop/play) and more sensitive and car feels like its alsmot supercharged at 4k now!
2. H&T (which was a bit hit and miss before) is now perfect ie pedal is firmer and further out and this easier to blip
also I decide the little nut like piece in my vid above was supposed to clamp onto the end of the rubber boot .. so that where it is now