What can I expect code 43 = (Fuel Supply) to be on a 91 accord. Any had this code before. Fuel pump, fuel injectors, fuel filter.

 

How does it run? if i runs normal than it could be a bad O2 sensor.

 

Yup runs normal, its a soft code. The code stays off until brobably 5-10min until I start driving and comes on. At first I thought it was the IAVC or IAT since sometimes at idle there is a steady abnormal idle that jumps 100-200rpm, but checked code and read code 43.

 

its a bad 02 sensor

 

Consider the code to mean the engine is running rich; or the O2 sensor is reporting that condition. I wouldn't rule out the O2 sensor but check the basics, plugs, air filter, pull the vacum hose from the FPR and make sure it isn't full of gas,
IACV stuck closed, throttle plate totally full of crud.
We used to call it the "dreaded" code 43.
The code Actually means there are unburned oxides being detected.
I think the true meaning was lost in translation from japaneese to english. LOL

 

Cool thanks guys Ill look more in to it tomorrow.

 

Yup its a tricky code to diagnose. I had the same problem with surging idle and it wasnt the IACV or any vacuum leaks, it was the valve on the intake manifold the one thats before the intake and underneath. Theres a screw in there that was loose so we tightened it and the idle went back to normal. I also had a code 43, and my car was bogging every so often. So I changed the cap and rotor and that helped because they were finished, but it still seems to bog a little. Code 43 is the fuel system and I have just recently changed the fuel pump and filter, but it will still throw the code. So I guess the only thing to do is to break it down into pieces with the fuel system and that could be a number of things

 

Does a code 43 also Cause the ECU/TCU to not let the transmission pull? In other words, I have a code 43, my car will not move after a few minutes in gear.