For the past two months, my son’s ‘88 non-turbo 245 occasionally fails to start after sitting overnight. When failing, it turns over briskly, has good spark and fuel (after cranking awhile, you can smell gas, and the plugs are wet when pulled.) Newish fuel pump relay also clicks over, and when triggered manually, starts the pump. We changed the distributor cap, though it and the rotor looked fine, as did the coil connections. The plastic Hall-effect connector at the distributor is not broken either. On occasions when the engine does start, it fires at once and runs perfectly--no stumbling at idle, good mileage, no smoke, no carbon in the tailpipe. Once running, it will restart easily all day. Sometimes there’ll be no trouble for a week, then, always after sitting overnight, it won’t start. Cold and humidity seem irrelevant; ditto fuel tank level. We’ve checked many things with the usual tests--including AMM, fuel pressure regulator, fuses (also the 25 amp fuel pump fuse and white holder under the hood). The rear coolant temp sensor shows correct ohm/ temp specs. Cleaned the throttle body in June. IAC was cleaned last winter, and smooth idle suggests it’s OK. In February the car had a faulty manifold ground, causing it to run rich and stumble, but that was repaired, and I cleaned the connection again to be safe, as well as the big battery ground cable at its block terminal. The infamous wiring harness was replaced by the PO, and looks fine. I’m guessing this is an electrical problem, but where? Thanks!!