Try pulling a screw driver in the gap of the hood release handle. It should help take out some of the slack. You will still need to push down on the hood to release it. Most likely the tension spring is shot and therefore needs to be replaced or you can take some of the slack out buy using a wire swedge.
I also had this problem... It means the cable stretched. What I had to do was pull the lever like you would opent the hood and then reach up behind the lever and grab the cable with a finger and pull on that. This will then pop the hood open. Once you have the hood open put a zip-tie or two on the end of the cable knub so that you can open the hood up like normal.
Have somebody hold the hood release cable in at the handle while you close the hood. If it works, your cable may be over stretched.
the cable is either stretched or broke
get a pair of pliers and grab the cable attached to the the hood popper and pull while pulling the hood lever it should pop open
Our 2004 Saturn Vue hood release can be opened (if the cable is not broken) by disconnecting the cable from the back of the release lever, grabbing the ball on the end of the cable with some large pliers ("channel locks") and pulling hard. A metal "wire keeper" bracket clamped to the cable end under the hood to serve as a spacer and the release lever works.
If the cable for opening the hood will not open it on a 1997 Saturn SL, put the car on a hoist. Then use a pole to trip the latch for the hood. Lower the vehicle, then open the hood all the way. Repair the cable before closing the hood again.
Under the hood
The 2003 Saturn Ion OBD 2 port is on bottom edge of dash; above hood release
To repair a hood latch cable on a 2003 Hyundai Elantra, you have to take it to your local mechanic or dealership. The hood latch cable should only be reconnected with an experienced hand. While you can use wrenches and screwdrivers, the latch cable may come loose again.
I dont belive you can; it may have stretched, so I would suggest you replace it before it breaks and locks your hood down.
I have the same problem with a 2003 Saturn L200. My mechanically inclined brother showed me how to open it. I don't know if it'll work as well on a Civic but by reaching under the front of the car, between the bumper and radiator, and pulling the cable the hood pops open. Everything I've read on the net says that replacing them is a royal pain so I'm just going to have it replaced somewhere. Hope this helped.
How to open of my BMW 745LI Yr 2003 hood ,whose Hood latch is broken while tried to open the hood