You should be able to get the codes yourself.

Go to www.autozone.com . Click on the "free repair guides" link on the right.
Put in your car's info. Keep clicking on links for the repair guides until you
get to the link that says, "Driveability and Emissions Controls." Click on it,
then click on "Trouble Codes." This page will tell you how to read the codes and
provide other troubleshooting info specific to your 90 Accord.

Maybe throw a bottle of Chevron Techron (about $6) into your next near-empty
tank of gas and re-fill the tank. This is supposed to help clean fuel injectors.

Updates welcome, as all these posts go into an archive that may help others.

Good luck.

"roshan" <aiyoo2@aol.com> wrote
> Car is a 1990 accord, 5 spd LX with 310,000 kms.
>
> It always starts fine, but lately after driving about 7 minutes it
> starts bucking and if I put the gear in neutral the RPMs are very low
> about(150).
>
> I also get a check engine line come on when the bucking occurs.
>
> (Btw, the bucking started after I got a new(used) alternator installed
> (by the dealer), would there be a connection?)
>
> I suspected a fuel problem as I also had a fuel line leak. I fixed the
> fuel leak
> and yesterday I also put a new gas tank and fuel filter. The mechanic
> mentioned that the fuel filter was really clogged up. (I hadn't
> changed it in 4 years).
>
> Anyway, my question is could it be that the fuel injectors got clogged
> up, due to the crude in the filter?
>
> I suppose I should get the engine code checked..
>
> Could it also be that the EGR valves are clogged? But then, how would
> it run fine for the first 7 minutes?
>
> Could it be a electrical problem?
>
> thanks for any pointers..
> Roshan