I don't think it's the latch. On my 140, the trunk lid would sit about 1/4 inch too high when the closing assist pump was malfunctioning. Removing fuse #9 for about 10 seconds and replacing would cure the problem for a few days. You'll probably need to replace the assist pump which is a common issue for these vehicles.

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2002 500SL(Black/Black)
1992 300SE(Black/Black)
1992 190E 2.3(White/Navy)
1999 VW Jetta TDI(Pearl Green)
1986 SAAB 900 Base 3 door(White)
1983 Porsche 911SC(Chiffon)
1977 VW Scirocco(DiamondSilver)