I got in the habbit of manually shifting my car when I wanted to go fast, because it absolutely would not stay in second gear on it's own. It would wind out ok in first, coulda been higher but was ok... then it would hit second, and before I even knew it, it was in third bogging along. My cold air door thing in the hood (1973 with the cold air door thing), never opened to my knowledge, but at the time I didn't put the two together. Once I figured out that a TH400 has an electric kickdown solenoid (people thought I was stupid cause I couldn't find the kickdown cable lol) I reached under there, unplugged the wire that goes to the side of the trans, and drove it with no change. Aha! my kickdown circut wasn't working, I probed the wire with my volt meter, had mom step on the gas and no volts. I read up in my manual and learned that the switch for the kickdown was down by the gas pedal, but i could never figure out how to get my head and arms down there at the same time....
Well, now is when I'm getting to all the "always meant to do that" things, and one of them is the kickdown circut. Does anybody know a good way to test the switch? Which fuse it runs off of? How in the world to get down there in the first place? (actually I'll have the drivers seat out to get to the seatbelts so that might be a bit easier)
I guess if I can't figure it out I could get one of those micro switches that is tripped by the throttle lever on the carb for turning nitrous on, and use that for my kickdown. But I'd rather not have to explain to everybody (at least the people my age) that I don't have "NAWZ" on my car even though it says "NOS" on the switch. ;)
any opinions or experience would be appreciated

 

Check The '73 Spot for the wiring and operation: http://www.corvetteforum.net/c3/vette73/cowlintake.htm

To test it, just turn the key on, crawl under there and press the switch. If working you will here the cowl door selonid click. On mine I sliped a piece of rubber tube over the switch arm to make it thicker which let the make better contact the the throttle rod.

tom...

 

Chris
click on the link in my sig./profile.
I hope the article on governor recalibration helps out.(you might like adding a console kickdown switch?)

 

I recently ran across the same thing you are experiencing on my 74. Thanks to members of the forum I was able to get both the switch and cowl induction unit working properly.

The switch is located near the top of the gas pedal rod. For starters, open your hood and righ next to the drivers headlight actuator there should be a connection from the car going from the vehicle to the wiring running down the inside of the hood to the cowl solenoid. Disconnect this switch to narrow down what is and what is not working. Once you locate the switch by the gas pedal, with the key in the on, not start, postion, pull the horizontal piece of the switch toward the rear of the car. You should be able to hear a click in the transmission, verifying that the transmission solenoid is working correctly.

Then hook a test light to the positive terminal on the wiring harness attached to the vehicle that you disconnected. Again pull the switch by the gas pedal back and see if the test light lights up. If it does you are in good shape. Reconnect the harness by the headlight actuator.(make sure that the connectors are firmly clicked back toghether) and again pull the switch and you should be able to hear the cowl unit open. If the test light was working, but the cowl solenoid does not open, you know the problem is narrowed from the wiring running up the hood or possibly the solenoid under the cowl. (My was not working initially, but after removing, cleaning, and making sure I had a good ground, it now works like a charm again.

If you press on the gas pedal, but the metal rod does not make contact with the switch lever try this. I am assuming that over the year from firmly pressin on the gas pedal that the rod gets slightly bent. I pulled up on the bottom of the gas lever, bending it upward a litle at a time until the lever made good contact with the switch.

I just completed this well past due project a few weeks ago and I am still smiling from ear to ear each time I step on the pedal. It is amazing how hard this thing shifts now, and I know longer need to manually shift
:)

Good luck and let me know if you have any questions.

Thanks again to the forum. I would not have benn able to do this with out of the help from all of the members.

 

Thanks a lot guys, in the morning I'll get out there and try the switch by hand to see if that makes any change. It would be cool if the gas pedal rod just wasn't striking the switch. Thanks again! :flag