hodshire

Hi, can anyone give me a starting point. I started my vette last weekend and let it run for about 20 minutes or so (ran nice), detailed it and covered it for a car show this weekend. Went out to go to the show on Saturday and it would just crank over and not start. I tuned it, changed the coil and opti spark 2 years ago (under 500 miles). I hear the fuel pump and smell fuel, so i am kind of stumped. Any ideas would be helpful. I have had the car for 4 years and no problems but the opti spark. Thanks!

BAMBAM3343

First test would be does it have fuel pressure and does it have spark.

jfb

Engines require spark and spark at the right time, fuel and air and in the correct ratio in order to start and run. Use a timing light while someone cranks to see if you have spark and spark at the right time. My money is on no spark since you smell fuel. Next, use a fuel pressure gauge on the shrader valve on the end of the right fuel rail to see if you have proper (36-42 psi) fuel pressure and see if the pressure holds for a long time with the ignition off. Rapid drop indicates leaky injector/s or a bad check valve at the fuel pressure regulator. Use a noid light (available at parts store) or an LED with a series 680 ohm resistor across an injector socket and see if you have pulsing during cranking showing that the injectors are being pulsed. Polarity of the LED must be correct.
New optispark or any other new parts doesn't mean anything, always suspect everything and prove by measurement that each system is working properly. Guessing and replacing is the dumbest and most expensive way to repair a car!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! !