I have a 2000 Honda Accord with 210,000 miles that I got for dirt cheap a couple days ago just to use to get around while I work on my actual car. Ran and drove when I got it but I already had the p1381 check engine light and was told by the guy I bought it from that he thought it probably just needed a new distributor. The car stuttered around 3,000 RPM and after a little research I decided that the distributor seemed like a likely solution. Right before I replaced it I noticed that the accessory lights were going on and off on my Dash and after replacing the distributor I had to jump start the car to get it started. I went for a very brief test drive and the check engine light didn't come back on. But after repairing the AC this morning and going for a longer test drive (charged battery overnight) the light did come back with the stuttering, I also feel like I may have noticed a small whining noise. After doing a little more reading it seems to me like the most likely issue is that my alternator diode has gone bad and this is why I'm having battery issues and the stuttering, the alternative is that the cheap distributor I put in could already be bad. I'm planning to just buy an alternator used with around a hundred thousand miles for around $50, to see if that will fix the issue. Just wanting some reassurance that I'm not missing anything and that my line of thinking is correct. Have a great day, thanks!

 

P1381 is for an interruption on the cylinder position sensor signal to the PCM. Recheck the new CEL code to make sure nothing new popped up.

 

Yessir, that's what I was working off of when I replaced the distributor, no new codes. Seems like others have had the light come on because the bad diode causes issues in the ignitions system leading to stutter leading to a bad reading from the sensor. Atleast that's my understanding