Sounds like you came across a lucky low mileage truck. As mentioned I would verify your ecu is working properly. You could also swap in a 91-93 3000gt/stealth sohc ecu to verify it's running properly. On a side note my MM was having a hard time starting. Would have to crank, stop, crank for days then hopefully start. Crawled under the truck and noticed someone had attempted to do some electrical work to my fuel tank. Needless to say that work extended into the tank too. I have finally fixed it and it performs like a pro.