I have a 2001 honda civic that recently started hesitating when reaching 4000 rpm. It also has two engine codes. P1298 & P1259. I am a diesel mechanic and could usually troubleshoot and fix problems on my own but, this problem is giving me a bit of a challenge.:confused: Any suggestions would be greatly appreciated. :) Thanks for your time.
Hutch.

P1298 leads to a problem with the headlights.

However, P1259 deals with the VTEC oil pressure switch (more likely the area your having problems) The diag is quite extensive. Do you have access to anything like a service manual, ie: Clymer's or Mithcell's manuals?

If your engine oil is low, some Hondas have a feature to protect the engine from damage around 4,000 rpm.

https://www.askmehelpdesk.com/cars-trucks/honda-civic-si-engine-cut-like-redline-4000-rpm-108357.html?highlight=4000+rpm