speed increases on its own

2003 BUICK CENTURY
58,000 MILES
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JERRY98
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  • 6 POSTS
What would cause my car's speed to increase after i let off the gas? the car runs fine other then that, I cleaned the throttle plate, and poured techron in the tank, checked vacuum hoses. The car has no trouble codes. The problem seems to be increasing. It doesnt happen all the time, but more often now i noticed the speed slowly increases instead of decreasing after i let off the gas. I'm usually going between 30-40 mph when i notice this, I occasionaly have a high then normal idle at start up also. Any idea's?
Apr 17, 2012 at 11:15 PM
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RIVERMIKERAT
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Is the return spring on the throttle properly installed?
Apr 17, 2012 at 11:29 PM
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JERRY98
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  • 6 POSTS
from what i can tell the spring is properly installed and original and seems to work ok by hand, the only work that has been done around the throttle body according to records was a canister purge control solenoid valve replaced back in 07.
Apr 17, 2012 at 11:49 PM
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RIVERMIKERAT
  • AUTOMOTIVE REPAIR CONTRIBUTOR
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So you can open the throttle by hand and watch it snap back closed? Have you had it scanned for soft codes. These won't set the CEL, and don't show up on all scanners. And you have to let them know you want to know about soft codes.
Apr 18, 2012 at 12:14 AM