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 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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