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TBI pedal feel

Mastiff

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I'm trying to get the accelerator pedal to feel right, which to me means fairly light pressure and no sticking. I was working on it a long time ago and ended up clipping one of the return springs. This makes it lighter, but maybe too light, like the engine vacuum can hold the throttle open a bit in some cases. It also seems a tad unsafe. Also, I notice that from dead idle at a stop, it's a bit sticky like you need to gun it a little to break it loose. It's not excessive, but a little annoying.

My questions:

1) Anyone ever heard of lighter return springs? It would be ideal to have two springs, but lighter than factory.
2) Can I replace the springs myself anyway? What's involved in getting the shaft out?
3) Does the sticking necessarily indicate worn bushings or something like that, or does the design rely on proper lubrication? I surfed around and saw no reference to lubrication of throttle bodies.
 
Pretty sure the throttle shaft setup on the TBI is like it is on carbs. The possibility then would be that the bore could wear out (primarily nearest the drivers side where all the load is) and under really bad wear conditions, throttle blades hit the TBI walls. I've heard of this, but never seen it even on ancient high mileage Q-jets. Loose throttle shaft bores are real common though.

The primary way to test all of this is to disconnect the throttle shaft from the pedal and TBI, and test each component individually to see where the binding is occurring. TBI should be pretty easy to tell.

I've never heard of any issues with the TBI throttle springs, nor an attempt to change the setup.
 
A very common issue for a heavy pedal in these trucks is the throttle cable. It wears a groove and the friction caused by it makes the pedal hard. Just pull the cable off on both sides, rotate it 180 degrees and re-install it. Should feel like new again
 
In my case, it feels light, but I only have one of the two springs. I think GM made the springs tough by design, but I don't prefer it. Modern vehicles don't have that feel.

A very common issue for a heavy pedal in these trucks is the throttle cable. It wears a groove and the friction caused by it makes the pedal hard. Just pull the cable off on both sides, rotate it 180 degrees and re-install it. Should feel like new again
 
A very common issue for a heavy pedal in these trucks is the throttle cable. It wears a groove and the friction caused by it makes the pedal hard. Just pull the cable off on both sides, rotate it 180 degrees and re-install it. Should feel like new again

x2


Also fairly common for the idle stop screw to back out enough for the throttle plates to stick in bore and cause a stiff pedal off of idle.
 
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