1990 honda accord throbs and pulses while idling or accelerating.. car drives fine until it warms up.

I would replace the ICM and coil, if they have not been replaced in the last 120,000 miles or 10 years:

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

These components break down under heat.

Is the ICM the main relay?

No. The Ignition Control Module (ICM) is located inside the distributor, while the main relay is located under the dash.

OK thanks Im going to check into that.. I was just wondering about the main relay because I replaced it like 5 years ago, and wasn't sure if I would fail that fast...

Main relays should last a good 10 years.

Good to know! And thanks I really appreciate it.. :)