Car wiring question

I bought this car three months ago and the other day, it quit on me. Reading your lessons I found there is no spark and no fuel. As indicated in the lesson, this shows I need a new computer. However, the computer is a little bit pricey and I want to be sure if that is the culprit. Is it possible also that all I need is just the efi relay?

Vehicle wiring advice

For almost all engines, if you have no spark and no fuel, almost always indicates a computer failure. However, in this model, both spark and injectors bare controlled by the ignition module called igniter. The igniter inturn is controlled by the computer so it is possible the igniter maybe the culprit here.

To check the computer, go to the computer terminals and check these terminals for power: pins +b and e1. You should have power there. Then check pin MREL and pin BATT that are used to power the efi relay. If you do not have power on these last 2 pins, then definitely, the ecm is bad.

One quick way to check if the ecm is bad is by using your dash light. When you turn your key on, there should be power of “check engine” light and quit. If the light fails to come on at all then for sure the ecm is no good.

Notes

The efi relay is use to power your fuel pump but the injector gets its power from the igniter.

Before replacing the ecm, just make sure the computer ground wire pin NE is not shorted.

When disconnecting any electrical components, always disconnect the battery negative terminal.

Whenever working under the dash panel, do not touch the yellow-taped wiring harness to avoid accidental deployment of the air bag which will activate even with the battery disconnected. Remember: you do this service at your own risk.