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Throttle/Bowden cable adjustments

 
Old 05-31-2013, 02:03 PM
  #31  
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Originally Posted by Jeff928S4 View Post
My car is a Canadian version, does that mean it's supposed to drop to 0?

Went out at lunch and tightened the throttle cable and loosened the "to pedal cable" (I figure that will help it "bounce back/snap" so I get the second click when releasing the pedal).

Now, when I lift my foot completely, the MPG dropped from 39 (for example) to 10, then instantly to 0.0. The next few times it didn't do it, then it did it again. I must be juuuuust off on the adjustment.

I need to put someone in the seat and press the pedal so I can hear if it is clicking when it is released with the pedal vs moving the throttle under the hood - that way I don't have to keep adjusting, then driving, then adjusting....
Read my description of how to do this.

If the throttle cable is affecting the idle switch....you are doing it wrong/have something wrong.
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Old 05-31-2013, 02:19 PM
  #32  
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Originally Posted by GregBBRD View Post
If the throttle cable is affecting the idle switch....you are doing it wrong/have something wrong.
I thought the whole point was to get that "click" of the idle switch by adjusting the throttle cables. How can the throttle cable not affect the idle switch?

Just a few quick questions re your description...

"Disconnect the kickdown cable" - is this the "bowden cable"?

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.


After this is done, will re-adjustments to the firewall adjuster be possible or is that the set point for the "to throttle" cable?
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Old 05-31-2013, 03:13 PM
  #33  
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Going back out again to try and line that click back up. I am noticing that when you pull the throttle plate to the left to get the click, then release it to get the click - that's fine and dandy, but when you actually push the accelerator, the plate doesn't "snap" back as far as if you do it by hand. The long run of the "to pedal" cable seems to leave a ever-so-slight discrepancy.
I think I said this early in this thread. Either the cable section to the pedal or the pedal pivots are sticking and need lubrication and/or that section of the cable needs to have a bit more slack to insure that the throttle plate returns to the idle stop and the TPS idle switch closes when you release the accelerator pedal. A frayed cable to the pedal with a few broken strands hanging up on the cable sheath would potentially cause this as well, although I personally have not encountered that.
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Old 05-31-2013, 04:21 PM
  #34  
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I was down under the pedal taking a peek and it does seem the pedal itself isn't popping completely out. Gonna lub it up and see if that helps.

After another adjustment, the car now drops to 0.0 mpg on the digital display when I release the pedal.....thing is, I've lost that "snap" I had before (due to the "to pedal" cable being really tight).

Gotta keep adjusting - but at least now the idle switch is being hit in both directions.
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Old 05-31-2013, 04:26 PM
  #35  
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So subscribed to this thread and so plan on doing these adjustments from scratch...
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Old 05-31-2013, 04:33 PM
  #36  
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Originally Posted by Jeff928S4 View Post
I thought the whole point was to get that "click" of the idle switch by adjusting the throttle cables. How can the throttle cable not affect the idle switch?

Idle switch is adjusted on the bench, before the throttle cables are even in the same room. There's a mechanical idle stop that needs to be hit....each and every time. The idle switch is then set so that it clicks each and every time the throttle passes to and from that stop.

Just a few quick questions re your description...

"Disconnect the kickdown cable" - is this the "bowden cable"?

Cable to transmission. It's the cable that operates the kickdown mechanism. It is not a Bowden cable.

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.


After this is done, will re-adjustments to the firewall adjuster be possible or is that the set point for the "to throttle" cable?

That's the only adjustment for the throttle cable from the pedal. When you are completely done and all of the cables are hooked up....you may need to "kiss" this adjuster to get the spring to do the correct thing. The spring is the key....it is there so that you can have full throttle at the butterfly, both before and after you hit the kickdown switch. Without the spring you'd either not have full throttle before you hit the kickdown switch or you would be attempting to break the cable, each time you hit the switch.
See if this helps.
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Old 02-08-2016, 02:34 PM
  #37  
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Been trying to correctly adjust all the cables on my '86 Auto. I do not have a "cable to Throttle" the 86 has a hard link from the assembly (at the front of the engine) to the throttle plate. I have assumed using the same order of adjustment in this thread but the transmission does not seem to be shifting at the right time. i have adjusted the throttle link first but am completely out of adjustment and the click from the TPS still takes at least 1/4" of movement before I hear it click. Is there a different sequence for the 85/86 MY ?
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Old 04-21-2018, 11:05 AM
  #38  
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Originally Posted by GregBBRD View Post
OK guys. Let me see if I can help.

Disconnect the kickdown cable.

Disconnect the throttle cable.

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.
Hi Greg;
im taking another look at my 86.5 setup. This method applies for my MY as well?

thanks

Mike
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Old 04-25-2019, 08:19 PM
  #39  
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Originally Posted by GregBBRD View Post
OK guys. Let me see if I can help.

Disconnect the kickdown cable.

Disconnect the throttle cable. the cable from quadrant to 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. how is this done with a 5 spd. car? relationship of compression spring?

Hook-up the throttle cable to the engine. again, guessing this means hook up the cable from throttle body to quadrant?

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.) not understanding "almost full throttle?" 7/8 of the way down?

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. the cable from pedal to quadrant?

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.) for 5 spd where should this be on the floor, or near the floor?

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! is the compression spring only important on automatic cars? what role for 5 speeds? You should have full throttle (butterfly opened completely) with or without the kickdown switch activated..

Start the car. It should idle.
questions above in red. resurrecting this thread and hoping greg and others can explain the difference on cable adjustments for 5 speed cars.

spent a good deal of time searching threads about cable adjustment and can't find any dedicated threads for proper adjustment of cables on manual cars. getting confused by the reference to the kickdown cable, and compression spring. I assume it would be even easier since 5 speed cars only have two pertinent cables. (not counting cruise)

some threads emphatically state you should set up the throttle body to quadrant cable first, and others say pedal cable first? once the large black adjusting screws on the cables are set up, are the threaded ball ends used for fine tuning?

if there is a thread that I have missed, please point me in that direction.
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Old 04-26-2019, 07:02 PM
  #40  
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anybody able to clarify accelerator cable adjustments on a 5 speed? is there a section in the WSM that covers this?
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Old 04-28-2019, 09:38 PM
  #41  
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Personally, throttle cable for MT cars are simple. You need some room for expansion of the engine when heated to ensure the idle switch still clicks when the accelerator pedal is released but also need to be able to hit the full throttle switch. Somewhere we have the info to put a multimeter on the correct connections on the LH to test but I've never had trouble hitting full throttle switch...some people like to adjust it so there's zero slack...gives a great pull on the 86's with just a little throttle but again risk here you want to be sure no matter how much expansion has occurred the idle switch always closes when pedal released.

Party on.
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Old 04-29-2019, 10:24 PM
  #42  
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today I adjusted my cables (new) with the engine warm as follows: prior to adjusting, idle contact as well as WOTS were working properly. my quadrant to pedal cable had a great deal of slack,
so I tightened that up with the black cable nut at the firewall so there was no slack at all, I lost proper idle contact operation, so I loosened the cable a few turns and all good. both idle contact
and WOTS work as they should (hammer tested). but they worked fine before, so I am not sure what benefit I gained.

my quadrant to pedal cable has "some" slack in it and wonder how much slack is OK? should it be taught? (I tried over and over to get all the slack out, but each time I lost the ability of the throttle cable to return the idle contact switch to closed position. and I played with the adjustment of this cable as well, but no luck)
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Old 05-23-2019, 10:57 AM
  #43  
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Thanks for this post. Just browsing and came upon it.

15 mins work and car transformed !

Before: She always very reluctant to downshift.

Now: adjusted 'Gas Pedal' Cable to get full throttle, and, then 1 full turn on the Auto transmission Cable, road test, and then 1 more full turn.

New car - for free! Thanks, Peter
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