Rep Power: 0

I just got this civic and the check engine like is on and it was a rocker arm code and 02 sensor. It wont rev past 4k in neutral or in any gear. its weird though bc when i first start it its fine i can rev it wide open but before im too the end of my rode it does it again. ive read alot about this problem and know alot about hondas but im in need of some help. ive ran gumout and seafoam, i just got an oil change today, ive reset of ecu. ive cleaned the vtec seloniod gasket, i have no power issues so im confident it isnt my ecu or bad connection anywhere or grounded wrong. it does have a swapped engine just another d17a2 like original motor (previous owner blew 1st motor). motor only has 50k on it. my fuel pressure is fine, it doesnt need a tune up, the only left is the vtec solenoid itself, i dont think the valve itself cant really malfunction its just a pin and spring. so im thinking its the valve timing oil pressure switch

 
Rep Power: 0

I know almost nothing about this, but I had to ask, did you replace the 02 sensor?