P1259 vtec system malfunction

[ridestreet84]

Ok as some of you may know i just had a replacement engine put in my car, now when run to the top of 4 gear or even higher in 5th i get a check engine light i check the code and the only code that was thrown was the P1259. Im not sure what could be causing this to happen could it be that the timing is off. Also it fells sluggish up in the higher speeds. Could this be from my Vafc, but i didnt have any problems with it with my old engine. Thanks for the help

[GScivic7]

well, the reason it seems sluggish could be the fact that it isn't crossing over into VTEC. First thing I would check is oil pressure.

[ridestreet84]

i know it is crossing into vtec and oil pressure is fine i have my vafc telling me its crossing over

[GScivic7]

Check your VTEC oil pressure switch.

The way the VTEC oil pressure switch works is that it is a normally closed switch. The ECM sends a voltage to the switch and expects the voltage to go through the switch to ground. If the ECM reads a voltage on that circuit when the VTEC system should not be operating, it will turn on the "check engine" light and set a code. This code will be a P1259 on a vehicle with OBD-II. So if it isn't reading the voltage going to the ground, then it may think the vtec is activating when it shouldn't be. That's why it sputters around those RPM's.

[ridestreet84]

i will have to do that thanks ill keep u posted