A steady on "Hold light" means you pressed the hold button next to the shift lever, repress to disengage.
A flashing "hold light", usually accompanied by the flashing check engine light means the car is in limp mode.
Limp mode stops the transmission from switching to forth gear and engages at 35 mph.
Check the Manifold Absolute Pressure sensor wiring, should have 5volts between the outer two wires with ignition turned on and the middle wire to outside wire voltage should change 1-5volts when you start the vehicle, also check the vacuum line for cracks.
Check the Throttle Position Sensor connector.
If both are good remove the plastic cover from the top of the engine and you will see the Camshaft Position Sensor between the camshafts on a 2005 or earlier Aveo disconnect the plug check the ohm reading between the pins it should be between 460-620 ohms.
If none of the above finds the problem then it probably needs a relearn procedure on the cam position sensor, this can only be done at a dealership.
Disconnectinng the battery for 15 mins usually resets aveo service lights if the problem is still there the flashing hold light will come back on.
2008 Chevy Aveo hold 11 US gallons.
12 Gallons
I have a 2005 and it holds about 12 gallons.
The hold light refers to the hold button on the shifter module. It means the transmission holds the lower gear revving up the rpms and won't shift to the higher gear. Seeing the light means the button has been engaged. Push it to turn it off
Remove the bolts that hold down the battery, remove the negative, remove the positive, and then pull it out. To install, do the following steps in reverse order.
4qts
10 gallons
open the hood there two clip that slide up they hold base light houing. open the hood there two clip that slide up they hold base light houing.
Practically speaking, my 2006 LT holds about 12 gallons. This page says it's 11.9. http://www.motortrend.com/cars/2006/chevrolet/aveo/specifications/index.html
Remove the screws that hold the covers in place. Replace bulbs!
To change the front signal light on a 2006 Chevy Express van, remove the bottom plastic cover that runs along the grill. Pull the push pins that hold the light in place. Remove the bulb and replace with new.
from what I gathered, the hold button keeps it in a certain gear while cruising on the freeway, so it doesnt always shift. I dont know what use that will be.