The other day I was going out and put some stuff in the trunk. When I went to shut the lid, it didn't catch. Tried a few times and then took a different car. The next day I had a look to see if it was something simple. I checked the factory service manual and they have diagnostics for when it won't open, but not when it won't stay shut. I hear clicking when the switch is pressed, so I know the switch is okay. I think I'm hearing a relay near the glove compartment, and also clicking at the back when someone else pushes the button, but not the usual clunk I used to hear. Everything looked clean, but I sprayed some silicone spray in there and disconnected the connections and put some dielectric grease on them. When I put a screwdriver through the latch mechanism it slips in and right out and doesn't catch. Has anybody had this happen to them? Any ideas what could be wrong - solenoid? I did a quick check on RockAuto.com and didn't see a solenoid, so I hope I can get the part.

Alternatively, does anybody know how to modify it so that it opens manually with the key rather than electronically with the remote button?

Thanks in advance.

Best option is to replace it & I believe the part is called a trunk latch actuator.
Might even be able to find one from a local junk yard car.

Unfortunately, it doesn't appear the part is available at RockAuto.com or even gmpartsdirect.com. Most junkyards (at least around here) don't keep cars this old around. Maybe I'll try ebay. I've had good luck with them for motorcycle parts.

Interesting development - yesterday was an unusually windy day and since the trunk was not latched, it blew open. My wife saw that from the house and went out and closed it. Low and behold, when she closed it, it latched shut! She tried it a few more times and it kept working. This is baffling, but my best guess is by spraying stuff in there etc. it must have freed something up. I wish all my cars would fix themselves like this! Hopefully this is the end of it, but just in case, I'm keeping some rope in the trunk to tie it down in case it flakes out while I'm out.

Ha ha..Nothing like the wind & silicone spay to get latch working again!
Glad it'* back locking again...let'* hope it stays that way!

Use a bungee cord. It will hold the lid shut and stretch to allow you to reach in and open it.