2001 civic. 1.7 L manual. I bought the car, not running. It will start with starting fluid and stay running until I shut it off, but will not restart without starting fluid. Fuel pressure is good 38 psi at Key on, 44 and engine running. No codes or check engine lights on the scanner( tested by unplugging the air temp sensor, and the code triggered to the scanner ) Timing checked on the cam and crank. And cam sensor and crank sensor Both replaced. Ground strap checked, tightened and verified at multiple points on the engine. Verified for a good ground with a test light. All fuses checked with a test light and relays checked with a relay checker as well as swapped just for the hell of it. Fuel pump Primes for the few seconds when the key is turned on. And fuel pressure is good on the fuel rail. No initial fuel injector pulse is sent while the engine is attempted to be started. Verified with both a noid light, and by pulling the fuel injector rail, and not seeing a spray of gas. Once starting fluid is introduced into the intake, the engine will start and stay running. And the injectors spray like normal. 12.6 V on all injectors with Key on. but no ground signal is sent no matter how long the engine is turned over for. Until the engine starts using starting fluid and everything works as expected. Any ideas? I am at a loss