First thing realize that aging cars, especially twin turbo aging cars are fairly expensive for maintenance on a yearly basis. Luckily about 75% of the things that will eventually if not already need to be replaced are easily DIY'able.Hmmm..things to look for.Stumble under WOT.(could be a half dozen different sensors)Max Boost under WOT, Boost during cruise. Just pay attention to the boost gauge a lot.Floating during high speeds and dipping during braking(dampers)You said "lightly modded", is there a turbo timer, this could be a good sign as the owner was interested in the vehicles health. Ask for maintenance records.jrt8222 wrote:Fixin to buy a 91' 300ZX TT with 87k miles on it, lightly modded. The exterior is in great condition but I dont know jack about Z engines. Ask me about a honda and I can tell you but I honestly dont know what to check for as far as what a car with X amount of miles on it. Any ideas? Someone said Fanbelts on Z's but other than that what should I check for? Help me out here guys (girls) need some pointer so I dont buy a lemon. :help