I recently purchased an 89 240sx coupe 5 speed. Seeing that I got it for only 330 bucks, I wasn't too picky about the condition.
The selling point for me was that even though she had been sitting untouched, unmoved, un started since before the winter season in late 2001 she fired up right away, first try. no boosting no nothing. All fluids were checked before hand and checked out good. Can you say reliable? I think my story speaks for itself on these cars. Horrible exhaust smell from the old gas that was sitting in the tank, and thank god it was near empty.
Things to look for, that I only started lookin at now that I have bought the car and never checked for them before hand are and as some mentioned above:
1. Timing Chain, its guides are notorious for failing in early years of 240s', leaving the chain to be guided by the guides' mounting studs, which spells certain future motor catastrophic failure unless you get it repaired. (which is what i have to do)
2. Rocker Panels, yup mine has problems there as well, about a 2 foot section on both the passenger and driver side towards the rear wheel is rotted beyond recognition. That'll be sanded cutted bondo'd and possibly a side skirt add on to cover up the part of the rocker that will be missing.
3. Early model 240sx's had a seatbelt recall, the buckles seemed to bust up and the functionality of the release button was gone. This is a recall that to this day has not been performed on my car, and Nissan has verified with me that it will be honored.
4. Bushings, theres alot of them and alot of them that fail with high miles and/or age. My car sat for quite sometime, and it would appear on what used to be grass that eventually perished from the 240 blocking the sun and rain from it. So yeah I got some bushings to replace, and also check the tie rod ends, you don't want those snappin and havin your car disco off the road and kissin a tree or some other inaminate object.
pics of my lil prize are on the webpage below if you care to browse through them
But yeah I can say reliable alright.