Hey everyone. Ive got a '90 Accord EX 250k 5 Speed. So recently my CEL turned on throwing a 20 and 43 and had a little trouble with loss of power after the CEL illumination. I am not sure what the code 43 means exactly. I have searched the forums and cant find a straight answer. Some say its a problem with the Fuel Supply System, others a O2 sensor. I am confused on what this means. If it is a O2 sensor where is it located? My repair manual says under the exhaust manifold? Took the heat shield off and cant find it there. Where else could it be, and is there more than one?
Any help would be appreciated.

 

The Dreaded code 43.
That code explination got lost in translation;
it means the O2 sensor is reading unburned oxides, or the sensor is going bad.
So you get the code if there is any reason the engine might be running rich, old spark plugs, plugged up throttle body, leaky injector, etc.
But the most common problem at that age of car is the O2 sensor itself.
Other codes at this link;
https://www.hondaaccordforum.com/for...ad.php?t=32718

 

Ok, so I've replaced the fuel filter and O2 sensor. The problem went away for a couple of days, and now its back. Ill check the other things you've mentioned and hopefully one of them will be the fix. Thanks for the info HondaDude.