I have a 1990 honda civic DX 1.5 liter dual port fuel injected civic that won't start. I have replaced the fuel filter and fuel pump. I have checked the fuel flow to the throttle body and there is fuel flowing when I turn the key on. However it will not start. I have poured a small amount of fuel down the throat and the car starts and runs until the fuel is used. Where should I look next? Is it a problem with the fuel pressure regulator, fuel injectors, main relay, or some other issue? Please help.

On the surface, it appears to be a fuel problem. However, I still suspect it's electrical related. I would replace the Ignition Control Module and see if that solves the problem. It may be that the car sparks fine, but it really is not firing when the ECM wants it to. The timing of everything has to be precise. I may be wrong, but that's what I'd try. This link may help:

https://www.askmehelpdesk.com/cars-trucks/faq-how-troubleshoot-repair-maintain-hondas-selected-other-vehicles-46563-4.html#post265896

I assume there are no codes and the CEL goes on and off normally. If the problem persists, then I would focus on testing the injectors. The fuel systems on these cars, however, are very reliable, especially if the CEL doesn't stay on. This link may help you diagnose fuel system problems:

https://www.askmehelpdesk.com/cars-trucks/faq-how-troubleshoot-repair-maintain-hondas-selected-other-vehicles-46563-7.html#post1245523

How do I check the codes if there are any? Also where is the ECM?

. To check for codes:

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

. ECM location:

https://www.askmehelpdesk.com/cars-trucks/faq-how-troubleshoot-repair-maintain-hondas-selected-other-vehicles-46563-3.html#post235038

Thanks I will look into it and hopefully get this civic on the road again

Great.

U need to pull back the carpet front floor board passenger side you'll see a medal plate with a hole that's where u will see a red flasing light count the number of flashes it can flash multipule codes or just one code there will be a short pause in be

The computer is flashing 10