I've gone through that dilemma with my car a couple of times. How long have you owned your ZJ? My car ended up staying both times I thought about selling it because of two reasons. my grandmother gave me the car after My grandfather died; it was his car. I've also owned the car for 9 years and have a lot of blood, sweat, tears, and money into it which I'll never get back.
I've had her a year and a half now. Lots of blood, sweat, and tears, and I figure by now I'm between 4 and 5 grand into her. On top of that, a ZJ was a childhood dream car. It's been something I've loved since day 1. And then there's a real kicker: My dad had an affair with this wonderful woman named Holly, at the end of the 90s, when I was a little kid. Things didn't work out of course (she was also married) but I have only fond memories of her and her family. And her Moss Green Pearl 1997 Jeep Grand Cherokee Laredo 4x4. Down to the option, Holly had the same exact Jeep I have, and every time I sit inside of it, I have a small nostalgia trip. It reminds me of good times.
But then I have to ask, how much more money can I spend on this thing before it's just not worth it anymore? I mean, $20,000 to replace everything is right out- I could buy a 2012 Laredo for that. But even as little as $5000 to get it running right again- I'd have no guarantee it'd stay that way, and I just know something small would break and the cycle would repeat. Of course, if I sell it, with some work, my best estimate is I can get 3k out of her. And that's with a few hundred dollars more work and parts. I'm gonna end up severely tits-up on this financially, no matter what. If I sell it, I'm gonna be heartbroken at losing my baby, but if I keep it I'm gonna be constantly stricken with worry about the next thing that breaks and having the money to keep it running. I'm already losing enough sleep as it is.