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Tim's Auto Repair
Tim's Auto Repair, mechanic
Category: Chevy
Satisfied Customers: 15762
Experience:  Have owned a repair shop for 25 yrs.
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2001 Chevrolet Venture: van is accelerating at 45 miles an hour

Customer Question

My 2001 Chevrolet Venture van is accelerating at 45 miles an hour sporatically. What could be wrong?
Submitted: 6 years ago.
Category: Chevy
Expert:  Tim's Auto Repair replied 6 years ago.
please explain..what do you mean when you say it is accelerating?
Customer: replied 6 years ago.
It just picks up speed while driving down the road. I don't even have to touch the gas pedal. It also will rap really fast when it is first started. I shut it off and restart it as much as 5 times until it will idle correctly. Then as I'm driving down the road it may just decide to speed up. Sometimes it will run fine, but the problem seems to be getting worse as time goes by. I had the service engine light come on a couple of times and was told when I had it checked at an auto parts store that the code was the oxygen sensor, bank 1. My son says it's not the O2 sensor. He thinks it's the throttle body position sensor.
Expert:  Tim's Auto Repair replied 6 years ago.

ok

strange,

sense the throttle is cable operated on this model,,i don't see how this could happen..i agree with your son,that it isn't the o2 sensor ..for the engine to rev like this ,it would need to get air,the only thing that i can think of that may cause this is the iac[idle air control]valve

thanks

 

 

Service and Repair

IDLE AIR CONTROL (IAC) VALVE REPLACEMENT

REMOVAL PROCEDURE


 

  1. Remove the canister purge valve.
  2. Disconnect the idle air control (IAC) electrical connector.

 


 

  1. Remove the idle air control valve attaching screws.

 


 

  1. Remove the idle air control valve.

 


 

  1. Remove the idle air control valve O-ring.

INSTALLATION PROCEDURE

NOTE: The IAC valve may be damaged if installed with the cone (pintle) extended more than 28 mm (1 - 1/8 in) . Measure the distance that the valve is extended before installing a new valve. The distance from the idle air control valve motor housing to the end of the idle air control valve pintle should be less than 28 mm (1 - 1/8 in) . Manually compress the pintle until the extension is less than 28 mm (1 - 118 in) .


 

  1. Install the new idle air control O-ring.

 


 

  1. Install the idle air control valve into the throttle body

 

  1. Install the idle air control valve attaching screws. Tighten Tighten the screws to 3 N.m (27 lb in) .

 


 

  1. Connect the IAC electrical connector.
  2. Install the canister purge valve.
  3. Install the throttle control cable bracket.
  4. The powertrain control module (PCM) will reset the idle air control valve whenever the ignition is turned ON, then OFF. Turn the ignition ON, then OFF.
  5. Start the engine and allow the engine to reach operating temperature.

Locations View

Customer: replied 6 years ago.
My son still thinks it's the throttle body position sensor. You don't think this is the problem?
Expert:  Tim's Auto Repair replied 6 years ago.

sorry.i had a little computer trouble here

i wouldn't think it is the tps..this wouldn't raise the engines rpm

thanks