I have a 1988 honda prelude it turns over but won't start changed the ecm new plugs cap roter and wires the main relay seems to be working it clicks when I turn the key to the on position the check engine light is not showing any codes it just stay on please help I am lost

Since the Check Engine Light stays on, the problem is with the ACG (ALT) (S) fuse, in the underdash fuse box; ECM (perform the K-Test); Main Relay; or the Ignition Switch. Perform tests in that order.

. Check all underdash and underhood fuses with a test light or multimeter:

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

. Clean the main ECM ground, likely located on the thermostat housing.