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Proper accelerator pedal travel

 
Old 12-07-2018, 05:50 PM
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merchauser
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Default Proper accelerator pedal travel

waiting for intake parts and playing with my accelerator and cables.

Not sure about how the accelerator travel is suppose to be with pedal on the floor. my pedal travels all the way down, and then if I push a little more, it feels
as if I am hitting a spring/switch like on an automatic with a kick down switch. this is the last 1/2 inch or so travel of the pedal. is this normal on a 5 speed?

before the attachment at the quadrant, there is a spring on the accelerator cable. is this that what I am feeling?
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Old 12-07-2018, 06:22 PM
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hmmm was your car one of the uber rare, automatics that had faster acceleration than the 5 speed......??
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Old 12-07-2018, 06:58 PM
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merchauser
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^^^^^^^ wondering if you are a plant for roger???.....hmmmm lol

took the cable off the quadrant, and the pedal travels with no resistance at the bottom. so it is the spring on the cable at the quadrant that is
creating this effect.



what is the purpose of this spring? it is to keep pressure on the cable to hold it in position? thinking that I don't have the pedal cable adjusted properly and
I am not suppose to have that detent feel at the end of pedal travel?
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Old 12-07-2018, 07:32 PM
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in the photo above you will notice a small thin sleeve just to the left of the spring. in the photo below, of a new one,
that plastic piece is larger and like the tip of a bullet. is mine broken?



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Old 12-08-2018, 04:53 AM
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Originally Posted by merchauser View Post
in the photo above you will notice a small thin sleeve just to the left of the spring. in the photo below, of a new one,
that plastic piece is larger and like the tip of a bullet. is mine broken?



Paul, the yellow tapering plastic piece is a dirt/dust cover which is missing on your wire. I do not think the cover is available as a spare port or does anyone know better? I like some covers for my cars too.
┼ke
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Old 12-08-2018, 07:06 AM
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merchauser
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thank you Ake. at the upper rear of the pedal is a flat piece of material, at 90', which acts as a stop, when it contacts
the floor of the firewall. on the final 1/2 inch of travel, I have a good deal of resistance, before I reach the pedal stop.
I believe the inner cable is fully against that small white sleeve, causing the outer sheath to buckle, and putting that spring in
to the equation.

I don't think this is normal. can someone tell me that the pedal is suppose to travel from its rest position, to fully depressed
with zero resistance? (manual cars) and what is that spring for? none of the other cables have this spring?
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Old 12-09-2018, 07:55 PM
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does anyone know what the purpose of the spring is, on the cable from pedal to quadrant?
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Old 12-09-2018, 09:38 PM
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I'm not an authority on this, but I would suspect that it's to prevent damage to the throttle body, if someone buries the pedal, but to make sure that you do have 100% range, instead of having to adjust the cable shy of 100%.

Another possibility would be to slightly pre-load the throttle cable, so that there is no slack or play in the pedal feel.
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Old 12-10-2018, 01:24 AM
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I like Josh's first guess. I had mine adjusted so that I can just barely hear the throttle hitting the stop with the hood open. But then I wondered if that could cause damage and I dialed it back a little. Now I'll be tempted to max it out again.

Just out of curiosity I tested my current adjustment with it just shy of hitting the throttle body stop, and the spring does not appear to compress.
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Old 12-10-2018, 01:24 PM
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matt968
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This is the procedure I used for confirming proper tension of all the cables. It also explains the purpose of the spring......Thank you to Greg Brown.
Copied from a previous post:



Disconnect the kickdown cable. (Cable that goes to the transmission)

Disconnect the throttle cable. (Cable that goes to the throttle body)

Have someone push down on the throttle pedal to full throttle....without hitting the "full throttle" kickdown switch, on the inside of the car. The "compression" spring, on that cable, right at the throttle assembly, should not compress. Adjust this cable, at the firewall adjuster, until the compression spring is just ready to compress. This spring should only compress when the kickdown switch is activated. Adjust at the firewall, until these two things happen.

Hook-up the throttle cable to the engine.

Have someone push down on the gas pedal to almost full throttle.....don't have them "mash it"....just gently push down to right around full throttle. (Trying to not break that cable or do any damage, with this step.)

Push down on the short exposed portion of the actual cable, right at the throttle assembly, with your fingertip, and see if the cable has any "play' or movement. It should have some "play" if properly adjusted. If it doesn't, make it longer. If it has lots of play, make it shorter.

Now have your helper push the throttle to full throttle....without hitting the kickdown switch. Re-check the throttle cable with your fingertip. It should be tight and not have any play (the butterfly should be wide open.)

Now "mash" the throttle to the floor and active the full throttle switch. Nothing should change, outside....except the compression spring should compress. The compression spring is simply there so that the cable from the inside of the car doesn't break....when the kickdown switch is activated! You should have full throttle (butterfly opened completely) with or without the kickdown switch activated.

Now have someone hold the gas pedal on the floor. Pull on the kickdown cable as hard as you can...with your hand. Adjust the ball socket, until this cable snaps onto the ball.

Start the car. It should idle.

None of these adjustment should change your idle. If they do, there is something wrong....these cables have nothing to do with idle speed. Idle speed is set by a separate idle stop, at the butterfly, and then controlled by a separate idle stabilizer.

You can now go drive the car. You might need to increase or decrease the tension of the kickdown cable a couple of turns to get a perfect downshift at full throttle and "hold" that downshift until the proper rpms are reached......without hitting the kickdown switch! When you hit the kickdown switch, you should get a second downshift, up to 65-70mph.
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Old 12-10-2018, 04:50 PM
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merchauser
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matt, thank you very much for the great information about adjustments.

my car is a 5 speed, so can you post any additional info pertaining to the adjustment, and that spring and the relationship
to manual cars. is the spring irrelevant with a manual transmission? or do I want to use that last little bit of pedal travel
to engage the spring? and, at what point would I want the throttle plate to be fully open? before or after the spring is compressed?
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Old 12-10-2018, 05:50 PM
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Sorry. Unfortunately I do not know. And I realized after posting yours was a GT.

I had found a previous post with this procedure in it. It was written by Greg Brown. Maybe he can shed some additional knowledge for a manual and if you need to modify this procedure.
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Old 12-10-2018, 06:22 PM
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merchauser
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^^^ thanks again, matt. that was great info regarding that spring and the relationship with the kick down cable.

anyone care to jump in and explain if that spring has anything to do with manual cars?
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