The hood pull cable is intact, and you can feel movement of some kind going on below the sheet metal in the latch area, but the hood remains closed as tight as a clam. What to do?

Happened to me a couple of weeks ago. The 'washer' at the bottom of the spring can get stuck when it slides up the pin so that there is no lifting force on the hood. Someone has to pull the release while you lift the hood and lubricate the pin area inside the spring.

Takes two people to open a stuck hood. One pulling the lever from the inside and the other pushing down then pulling up REALLY hard on the hood. Once you get it opened first thing is to remove the grille. THEN figure out what is wrong.

The pull wire runs through a sheath. The sheath is supposed to remain stationary and is secured by a clamp(s). If the sheath is loose, then it is pulled also resulting in insufficient movement of the pull wire to activate the latch.
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1980 245 Canadian B21A with SU carb, M46 trans, 3:31 dif, in Brampton, Ont.

The cable lever adjacent to the lock can seize on it's pivot. When that happens no amount of cable pulling will release the lock. You might be able to get some Kroil or similar up there with an extension tube on the can and that may help free it off.

Taking this one step further. Assuming that nothing is broken, after you get the hood open lube the cable, lever and all other pertinent mechanical parts.

The latch assembly may have lost alignment from the securing hardware coming loose, or after many decades of Seattle rain, lost lube at the latch or inside the release cable sheath. Or the spring loaded pin secure to the hood may have moved around or lost lube or is coming unscrewed.

Or who knows the cause. I'm probably forgetting again.

One Method:
Ask someone to push down on the hood directly over the front center edge where the latch assembly secures together. As they push down, and it may take some downward force, pull on the release lever, than ask that person to remove the downward force they are applying.

Second Method:
Else, in the void behind the front (bar and) grille and in front of the A/C condenser, when underneath your 1991 Volvo 245, you can see the underside of the lower part of the latch assembly that is connected to the hood release cable.

The void may be covered underneath by a sort of plastic plenum that secures to to clips snapped or screwed, at the front edge, on to the lower cross member radiator support. The front of that plenum rests on the three rectangular hole in the front valance (below the front bumper). You need to remove this plastic plenum to get to the hood release cable under the upper horizontal cross member radiator support.

You can reach up to the right side of the hood release latch and see the actual cable sheath and the cable itself. The cable sheath is anchored near or at the latch edge and the cable protrudes and secure at the latch mechanism.

Pull on the cable from underneath.

The cable sheath at the end may have come unsecured at the end near or at the latch. So, you may need to pull on the cable.

Related, yet find more with search feature:
- https://www.brickboard.com/RWD/volvo/1604153/220/240/260/280/89_240_hood_pull_release_malfunction.html
- https://www.brickboard.com/RWD/volvo/1368298/220/240/260/280/hood_release_broken.html
- https://www.brickboard.com/RWD/volvo/645856/220/240/260/280/240_hood_release.html
- https://www.brickboard.com/RWD/volvo/898215/220/240/260/280/hood_release_cable_loose_adjustment_screw.html

FAQ Guidance:
https://www.brickboard.com/FAQ/700-900/BodyDoors.htm#HoodHingeLubrication
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One more thing to add to Kitty's post. If an assistant pushing on the hood doesn't help and you go to the panel underneath between the front crossmember and the bumper to expose the underside of the latch---use a straight bar (18" 3/8 socket extension works well) directly under the bottom of the "pin" and give it a hammer smack while the assistant holds the cable release. That will pop the hood if the problem is lack of lube or misalignment. -- Dave

Thanks guys.