Hard accelerator pedal

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Juan Cano

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Hi; have noticed (and wife noticed too last weekend) that the accelerator pedal is hard to push. There is no soft start to the pedal, so sometimes if you are not being careful, you push it and truck lunges forward because you gave it too much gas.

This has an Edelbrock Carb. I removed the spring attached to the cable and is the same result. Added a bunch of lubricating oil and the same. It almost seems like is the Accelerator Pump in the carb? Perhaps that is normal on an Edelbrock carb? BTW, what is the second cable below the accelerator cable for? (Such an ignorant fool!)

Have had it for a year, so is not a big deal to fix, just thought it could be something easy.
 

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dvdswan

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It could be the carb. But for my better understanding, you disconnected the accelerator cable from the carb and the gas pedal and moved it back and forth with your hand?

The bottom cable would either be a kickdown cable for the transmission if automatic or cruise control if equipped. Otherwise, I'm not sure on that.

I had a sticking accelerator cable but it turned out to be part of the plastic shield around the cable catching on sleeve for the cable.

It looked like this... The flared part had broken and would catch on the other part of the sleeve.

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wlwarnke

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The bottom cable is the TV cable for the 700r4 transmission.

Sometimes that cable or the valve it connects to inside the Tranny can get sticky.

Does the pedal feel normal with the engine off?
 

Bextreme04

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Disconnect the throttle cable from the carb and see if the cable moves freely and the throttle moves freely. Also, like William stated, the cap on your manifold vacuum port is split and likely leaking vacuum.
 

SirRobyn0

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Here's my thoughts. My first question is this a change or has it always been stiff?

Disconnect the accelerator cable and see if it moves freely. Disconnect the TV (trans) cable and see that it moves freely. There will be some resistance when pulling on the cable end but you should be able to do it with your fingers. If you see a problem in either of those you'll need to see if it is the cable itself or the component it connects too. If those seem normal disconnect the throttle return spring and see if the throttle on the carb moves freely.

I'll be frank, you need to make those checks before considering changing the throttle return spring but a hard accelerator petal is often subjective. The way you have it setup with the spring attached to big top hole in the throttle linkage the spring has the mechanical advantage, this is good safe way to set it up, and it is the way the edelbrock on my truck is setup. If you look at most of the Q-jets the spring is setup differently and the two spring (one inside of the other) setup like was used on the factory Q-jets leads to a VERY light soft petal that you are unlikely to achieve safely with an edelbrock. So if your comparing your trucks throttle to your wifes newer car or even a friends truck yours maybe much stiffer but perfectly normal.
 

PrairieDrifter

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My factory pedal would move fine without the carb hooked up, then once hooked up it was near impossible to push the gas. It actually got so bad the pedal twisted off lol.

I ditched the cable and went to a mechanical linkage. Smooth as BUTTER.
 

Frankenchevy

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I’ve had eddy carbs and not noticed a stiff pedal. The sniper I had, now that was stiff. It required a different linkage. That was due to 1:1 ratio between primaries and secondaries, but yours isn’t mech. secondaries. My guess is something is binding…

If everything seems to be operating normally, you can extend the throttle linkage for more leverage.
 

SirRobyn0

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@Frankenchevy I agree with your comment on eddy carbs, to me in the picture the return spring looks pretty beefy, but without being there it's hard to say and I don't wanna tell the guy to weak spring in and then it sticks wide open on his wife. IDK for some reason I've seen a few home installs at the shop with the spring up high and out to far making a stiff pedal. So that's the prospective I was coming from but yes I agree they can be set up with a much more normal pedal.
 

Juan Cano

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Wow, thank you so much for so many ideas to test. I will work on them this week.

And yes, the pedal has always been hard. It's only hard at first, then it moves well. Now it sounds like dirty bedroom talk.

And yes, probably comparing it to a 2021 Kia is not fair.
 

Ronno6

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Does the pedal act the same whether the engine is running or not? When the throttle plates are closed, a running engine's demand for air exerts significant side load on the butterflies, making off-idle movement difficult. If that is the case, wear between the throttle shafts and the throttle shafts rendering small movements really sticky..........
 

SirRobyn0

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Well that was worth the post!
I'm not really sure what your trying to say, but there is an obvious crack in your vacuum cap / plug on the carb in the picture, and Mike might be trying to save you from having to chase that down at some point in the near future. If you have already seen that and fixed it you could just say that....
 

WP29P4A

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Well that was worth the post!
Everyone else had all the basics covered so not much I could help with. It seems pretty basic, disconnect the spring and throttle cable from the carb and see what moves freely and what doesn't, fix the issue and put it back together. Looked to me like the return spring is huge, but I know phone cameras can distort some objects in the image that are closer to the lens than other objects in the picture, so I didn't mention it.

Your carb linkage will definitely move a bit easier if you lube all the extremely dry metal contact points shown in your picture. I don't think that spring is designed for a return spring on a carb, which I believe is why it's hard to get the pedal to start moving as you push it. After looking at your spring setup it reminded me that most of the factory springs back in the day were double springs. I believe factory return springs are designed to have a linear pull design so the pedal feels the same through out its travel. General propose springs do not.

Good thing your not family, I'm the kind of guy that would replace your cracked vacuum cap with a piece of hose and a whistle from a dog toy, when your not looking.
 
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