PGM FI light Trouble Code 1

[Honda1987]

Hi, I have a 1987 Honda Accord Lxi I am driving across country early next week. Problem is, PGM FI light trouble code 1 is lighting up. Already replaced O2 sensor and the light came back on.

Part was not Honda original, but was made from same company who makes honda part and put in different box.

Please help!

[Oldblueaccord]

Well you can drive it with the O2 not working but it will most likely run rich and it is possible to clog the catilytic converter over time.

I would check your wiring and make sure you dont have the wires switched.

wp

[ecogabriel]

You may drive the car as it is; the ECU would use a certain pre-programmed setting. However, your fuel economy would not be as good because it will be running rich (too much fuel)

You should check the wiring from the O2 sensor to the ECU. First check that the contacts in the O2 connector are clean. Then I would take the driver seat out and uncover the ECU. There are two (if I remember rights) big terminals with a maze of wires on each one. Each terminal contact is identified by a code (e.g. A1, B10, C2) Look for the service manual somewhere here; Autozone used to have a wiring diagram of the ECU connector that although it was for 88-89 models it will still be useful (those have two O2 Sensors plus other diff... ) whereas 86-87s have only one sensor (you have one, right?)
Get hold of the service manual as it walks you through the testing process; you only need a multimeter to check for O2 sensor signal coming to the ECU. No signal coming to the ECU may mean open wire or a non-working sensor...

Good luck

[G. White]

I had a O2 sensor fiasco awhile back. I went ahead and changed them both. However, when I did....I spliced some larger gauge wire in to replace the old stuff that was cracked and damaged. Bad idea....the O2 sensor signal is something like .04volts. So any minor deviation in voltage (i.e. larger gauge wire) threw off the signal and caused the code to flag again, even with the new sensors. Once I figured that out...I put the right stuff in and it worked like a champ.

Make sure you changed out the correct sensor. Then check the wiring...initially my problem was the old sensors wiring had cracked and was grounding out on the motor mount stud. You could peel back all the convoluted tubing that covers the wiring harness to the ecu and check that....but it wraps around the backside of the engine and is a pain in the ass. After that possible ECU.

Most likely its something simple. Good luck on your trip.