I have a 91 Accord that is getting a check engine light code of 09. I've replaced the distributor assm and checked the wiring from the distributor to the ECU for open/short. Same problem. So I assume the next thing is to replace the ECU.

The strange thing is the code does not happen when I start the car, or start it and let it idle and rev for a while. It occurs only after driving for a few minutes. And I don't notice any difference in performance before and after the code. Seems to run fine.

Has anyone experienced this error before? Any feedback or suggestions would be welcome. Thanks

 

I haven't replaced the ECU yet. Everything I've read seems to indicate that the problem being in the ECU is very rare at best, especially since a visual inspection of the ECU looks pristine, not even any dust.

I have read that this can be caused by wiring interference or a break in the wiring that is still making contact (so the signal gets dropouts). So I'm going to try running 2 shielded wires from the dizzy to the ECU, just to verify that's not the problem before I pay out for an ECU.

Again, any feedback or suggestions would be welcome. Thanks

 

Wow what are the odds huh, I have just recently ran into the exact same problem. Except my MPH gage goes haywire, 40mph 0mph 40mph 0mph My idol drops a bit only after the check engine light comes on, but if i turn the car off and back on agian it seems to run fine?

Also I've been having a lot of little electrical problems the past few yrs. Main relay needed to be replaced. Main switch for the Windows, right window rolled down but not back up. No running lights, replaced with a new light switch. Blower Motor for heat repaced twice, once with a old used one now with a new motor. And now this.

Could this be the main computer going out ?
-cB