I swappedy integra with a jdm b18c. The car strong and pulls hard but wont go past 6500 rpm. I have a code 21 for vtec but my vtec engages as it should and pulls but wont go past 6500 rpm. I am using the stock p73. I swapped ecu with a chipped p28 and still same thing.

 

Sounds like its the vtec spool solenoid valve, the JDM B series do not have them, jdm engines aren't equipped with an oil pressure switch on their solenoid. Try using a USDM vtec solenoid. check this link,

https://honda-tech.com/forums/honda-...witch-3047213/

 

Yes i bypassed the pressure switch and vtec still activates just wont go past 6500

 

Its in limp mode, is there any more codes? Try pulling the battery neg for a few mins and plug it back to reset the ecu codes. Are you sure vtec is activating?

 

Disconnected battery, reset ecu by pulling 15 and 7.5 fuse and still same thing code 21 right away. Yes vtec is activatimg

 

I think its the way you have it wired possibly, that's the only way the ECU will pop that code its a wiring issue. And im pretty sure your not activating vtec if your ecu has the limp mode and rev cut at 6500, most vtec activates at 4,800 rpm low cam and 5,800 rpm high cam depending on ECU, you might think you hear it or what not but im 99% sure your not activating vtec with that code on. Check your wiring again!

 

you have other issues.

 

Its a jdm solenoid so i have the solenoid wired directly to the ecu pic for vtec and yes im sure i can hear the vtec crossover its loud n clear that its activating