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Chevy S-10 takes off at 20 mph without touching the gas

i own 1994 s-10 and when i start it up and put it in drive, it takes off at about 20 mph without me touching the gas pedal. It is not a carburetor problem. We don’t know why it does this. We have been told that it might be a transmission problem. Do you have an answer to this problem?

It can’t be a carbutetor problem since you don’t have one. Is the check engine light on? What engine? By takes off… do you mean that the idle speed is very high?

What speed does motor idle in park? 800rpm?

Anytime I hear this complaint, the first thing I check is if there’s a problem with the Idle Air Control valve.

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Tester

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If the warm idle rpm is too high, suspect the idle air control gadget, throttle valve sticking, or big vacuum leak. One caution: Engines of that era often have a little air-bleed screw on the throttle body to adjust the idle rpm as part of a tune up. Don’t try to fix this problem by adjusting that screw. That’s only for fine-tuning, and if you adjust it to correct another problem the engine will never run correctly.

As for the transmission-involvment theory, first off do you have a manual or automatic transmission?