1994 Integra LS w/ 40,xxx miles on the new engine. Here it goes...

I tried to start her up and it sounds like she wants to start but just won't. I checked spark on all 4 plugs, they had clean spark. I put new injectors and fuel rail in. Battery, starter, and alternator work fine. When I turn the key all the gauge cluster lights come on as they are supposed to, I can hear the fuel pump whine for a few seconds--but my CEL light stays lit... Never blinks or goes off. I checked grounds in the engine bay and they are all tight and connected. I replaced the main relay with a new one from my local Dealership. Im clueless at this point. Ive read through a lot the troubleshooting guides on here and other places online and just can't seem to get anywhere. Anyone have any ideas? Thanks in advance.

. Check all under-dash and under-hood fuses with a test light or multimeter:

https://www.askmehelpdesk.com/cars-trucks/faq-how-troubleshoot-repair-maintain-hondas-46563-3.html#post252145

. Clean the main ECM ground on the thermostat housing.

. Perform K-Test on ECM:

Remove the MAP Sensor connector and turn the ignition switch to ON (not start). Using a multimeter, check for 5 volts going between the MAP Sensor connector's reference wire (+) and ground. As you look at the connector, this is the socket on the right. Really press the black test lead into a cleaned main ECM ground on the thermostat housing. If the voltage is low, it's probably indicating ECM failure. Most failed ECMs will record a fraction of a volt. To me, the K-Test is simple, elegant, and accurate.

The CEL staying on, which prevents the car from starting, is caused by fuse, ECM, main relay, or ignition switch failure.

Thanks, I appreciate the quick response. I'll do those tests and keep this thread updated.

Back from the dead..

The underdash fuses passed the test light. I also performed the K-Test and got a reading of5.1-5.2 volts. So I deduce the ECU works. My next step is to test the fuel pump but... When I replaced the injector o-rings I forgot to tighten one down and some fuel sprayed out. So I know its getting 'some' fuel and I can hear the pump kick on when I turn the key.

It sounds like the ECM has thrown one or more codes. Here's how to check:

https://www.askmehelpdesk.com/cars-trucks/faq-how-troubleshoot-repair-maintain-hondas-selected-other-vehicles-46563-6.html#post832012

This will likely lead you to the solution.

I jumped the connector and turned the key. The CEL lights up for 3 seconds, then off for 4 seconds, then on for 3 and off 4 etc. I saw no long/short flashes.
I sat and waited for short and long flashes for about 10 minutes about 4 different times so I don't think I missed any.

That may be a Code 1, problem with Oxygen Sensor #1.

Ahh,

Ignore the post above. I did the CEL test with the fuel injectors, IAT sensor, and MAP sensor unplugged. So many things to test I forgot to plug 'em all back in. I'll keep this updated, thanks for the help.