Throttle valve cable adjustment - need help, no upshift
Kings-x59
08-21-2005, 05:35 PM
'89 Astro 4.3L Z / 700R4 trans.
I did a rebuild on the throttle body and put a throttle body spacer under it. I did the TV cable adjustment as described in my Haynes manual, but no go. I used the spacers provided with the power plate to elevate the throttle cable / tv cable bracket.
The engine runs great now but the van won't upshift to second gear.
I must be missing something in the cable adjustment. Any help is appreciated.
I did a rebuild on the throttle body and put a throttle body spacer under it. I did the TV cable adjustment as described in my Haynes manual, but no go. I used the spacers provided with the power plate to elevate the throttle cable / tv cable bracket.
The engine runs great now but the van won't upshift to second gear.
I must be missing something in the cable adjustment. Any help is appreciated.
CD Smalley
08-21-2005, 05:54 PM
I'd guess that you have it overtightened. Especially since you just installed a TBI spacer. That surely lifted the TBI unit and thus pulled the TV cable further out than it should be. I'd guess you need to let it loose somewhat to compensate for the lift of the TBI spacer.
Kings-x59
08-21-2005, 06:58 PM
The first test drive I hooked up the TV cable with the stock adjustment. First gear the rpm wound up higher than normal and the trans slammed into second gear.
My understanding of theTV cable is limited -
As the throttle is increased the tv cable pulls outward. Does this increase pressure on a gradient or is it more like turning a switch?
Is the no-shift due to the pressure being too low or too high?
My understanding of theTV cable is limited -
As the throttle is increased the tv cable pulls outward. Does this increase pressure on a gradient or is it more like turning a switch?
Is the no-shift due to the pressure being too low or too high?
Kings-x59
08-21-2005, 07:02 PM
One other question:
When you say let it loose, do you mean adjusting towards the throttle linkage or away from it?
When you say let it loose, do you mean adjusting towards the throttle linkage or away from it?
CD Smalley
08-21-2005, 08:45 PM
It is a gradient rather than an On/Off switch.
When you adjust it, make sure the TV cable is sliding backwards towards the trans. You want to make the cable looser at WOT rather than tighter to adjust for your TBI spacer.
When you adjust it, make sure the TV cable is sliding backwards towards the trans. You want to make the cable looser at WOT rather than tighter to adjust for your TBI spacer.
Kings-x59
08-23-2005, 09:29 AM
Thanks CD,
I think I may have two problems.
The spacers for the cable bracket are about 1/2" tall, whereas the TB spacer is 1". I've come to learn that the geometry of the bracket, and rotation of the throttle linkage is critical for the TV to work properly. Given the disparity in the TB and bracket spacers, I think the geometry is messed up.
I think the cable might need replacing.
After reading some on the "self adjust" of the TV cable, I think I should hear a click or two, which I am not. Also, the slider should move some shouldn't it?
I think I may have two problems.
The spacers for the cable bracket are about 1/2" tall, whereas the TB spacer is 1". I've come to learn that the geometry of the bracket, and rotation of the throttle linkage is critical for the TV to work properly. Given the disparity in the TB and bracket spacers, I think the geometry is messed up.
I think the cable might need replacing.
After reading some on the "self adjust" of the TV cable, I think I should hear a click or two, which I am not. Also, the slider should move some shouldn't it?
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