My daughter's car recently quit working. We've replaced the fuel pump, relay, distributor cap, plugs and wires and she still won't fire up. We've sprayed ether into the intake and it fires for a couple seconds then dies. We've checked the injectors, all good there, got spark, but we're still at a loss. Any help would be greatly appreciated.
Turns over but won't fire up. on 1992 Toyota Celica
by cam7198 in Aurora, IL on May 24, 2011
ANSWER by patrick mannion , May 24, 2011
So many things can cause the engine not to start or stop running it is hard to guess at a cause without being able to do some diagnostic tests. An engine needs fuel, spark and mechanical integrity to run. (it must develop compression in each cylinder to start ie mechanical components must be in synchronization with each other, timing belt in proper order). The engine may have lost spark or fuel which could be due to any one of a number of sensors having failed or the fuel pump or related components are not delivering fuel to the fuel injectors. The engine uses many sensors to report engine temperature, air flow into the engine, crankshaft and crank shaft position sensors to allow the computer in your car to make calculations controlling fuel and spark to the cylinders. Check for fuel pressure (you will need a fuel pressure gauge and look up the specified fuel pressure for your vehicle). Remove the fuel hose that goes to the fuel rail and get a friend to crank over the engine to see you have adequate fuel volume (you should have approximately 1 pint of gasoline in ten seconds of cranking). Off course take proper precautions as gasoline is highly flamable. Next "listen" to the fuel injector. Using a mechanic's stethoscope (or use a long screw driver placing the handle end up to your ear place the metal tip end of the screwdriver against the body of the fuel injector), get a friend to crank over the engine while you "listen" to the fuel injector listen to each injector at the same point of the injector body. You should hear "click, click, click" as the injector is electrically opened and closed by the computer. If the injector is not being triggered you will not have fuel getting into the engine's cylinders. Disconnect the electrical connector at the fuel injector with the ignition key in the "on" position, (next position after the accessory position) you should have 12 volts at one of the two wires at the injector. This true for most vehicles but you need to consult a workshop manual for your vehicle to see that this is true for your vehicle. When the engine is running the second wire at the injector gets (triggered) grounded by the computer in your vehicle many times a second controlling exactly when and how much fuel gets injected into the engine. I have seen the coil provide spark but short internally and not provide enough spark, I have seen the rotors short.