1978 k30

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DoubleDingo

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81-C20 Silverado Camper Special-TH400-4.10s
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Carb'ed Vortec 350
Choke doesn't kick down the transmission, but it can limit throttle travel, not allowing the kick down switch to be activated.
What I meant by limiting throttle travel, is if the secondaries cannot open, then the gas pedal doesn't have enough travel to activate the kick down switch. If the choke is adjusted properly, all linkages should be out of the way so WOT is doable. If WOT is not doable, then no kick down switch activation.
 

Steelbuddha

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1984
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Smells like a vacuum-related issue from here. Confirm that the vacuum advance is working properly. Also confirm proper function on the transmission's vacuum modulator. Also make sure there are no other vacuum leaks. If that doesn't help, check function of your kickdown linkage.
 

DoubleDingo

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Smells like a vacuum-related issue from here. Confirm that the vacuum advance is working properly. Also confirm proper function on the transmission's vacuum modulator. Also make sure there are no other vacuum leaks. If that doesn't help, check function of your kickdown linkage.
@derekhisle There is no kick down linkage on a TH400, it's a kick down switch on the gas pedal under the dash. Do not look for kick down linkage, you will never find it.
 

Steelbuddha

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@derekhisle There is no kick down linkage on a TH400, it's a kick down switch on the gas pedal under the dash. Do not look for kick down linkage, you will never find it.
Okay, in that case, the operation of the switch. I stand corrected.
 

K20SM465

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Just report whatever fixes your issue. Sometimes when you get flustered it was staring you in the face all along.
 

derekhisle

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1978
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K30
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Just report whatever fixes your issue. Sometimes when you get flustered it was staring you in the face all along.
I'm planning on trying to do some digging into it this weekend I work fairly long hours during the week, so I don't have any time
 

Ricko1966

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Do you think that since I don't have the electronic choke hooked up Currently that that could cause it?
Why don't you have power hooked up to the choke? Do you have the choke fixed in the fully opened position. If not that explains a whole lot.
 
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derekhisle

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Why don't you have power hooked up to the choke? Do you have the choke fixed in the fully opened position. If not that explains a whole lot.
It's fixed fully open... I haven't had time or money to really work on it.I'm just trying to get some info.So that I know what my best move to make is before I start working on it
 

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