I recently got rid of my 88 prelude for a 2001, it has been running good until recently, the cel came on, I went to autozone code was for a knock sensor, then 3 days later the cel started flashing and the car started missing and sputtering but only at low rpm and speed, the car runs fine after about 2500 rpms, i then went to advance auto and was told it was a p1399 code and a cylinder 1 and 3 misfire. The plugs, wires, and cap have been replaced the knock sensor done and i'm still having the issue with the missing and sputtering, i have done several searches and corrected some of the things suggested. the CEL stays on and then will start flashing but will stop after about 2500 rpm and ideas what to check next??????????

 

Do this and write down all the codes you get.

https://honda-tech.com/forums/honda-prelude-4/how-retrieve-cel-atts-abs-4ws-dtcs-2553408/

Then go to this site to download the Helms manual.

http://www.spoonertuner.com/manuals

Turn to chapter 11 and start reading.

 

did that got cel code 71 and 73 cylinder 1 & 3 misfire got ABS light codes 61 ignition voltage and 81 central processing unit

 

That means your KS isn't giving a code anymore. Good. Now just download the manual and go read these pages.