Drove the car hard for little bit then did a sweeping turn at about 7K rpm then all of a sudden, no vtec...I had my car set up so vtec kicks in at 5500 rpm. I slowed down and tried to rev the car between 4-5K rpm, still no vtec. I have no codes either...I unplugged my ecu and will plug it in after this post (about 15 minutes later) and I'll find out if its fixed or not. Any suggestions?

 

check your oil level, or the solenoid itself might be clogged.

 

1) Oil level, its gotta be FULL. I'm talking at the upper mark on the dipstick.
2) Solenoid, Ok this is a 2 parter. A) take a wire (any wire) disconnect the grey plug on the vtec solenoid and touch the wire to the pos. battery terminal and the solenoid side of the grey 1 pin connector. there should be an audible click from the solenoid. B) If A checks out, remove the solenoid and clean the filter screen. (self explanatory)

3) Speed, the car must be going over 10 mph so the spedo must be working. that means the VSS has to be working. vtec is temperamental isn't it?

4) more oil, check the oil pan. if its dented POUND IT OUT!. this is why mine wasn't working. the pan was dented in far enough to hit the oil pickup for the pump to cause low pressure situation in the head, no pressure no vtec.

5) ECU Swap out to another ECU that you KNOW vtec works on.

6) Car must be at I belive its 80 degrees or higher so let car get to a normal operating temprature.

7) If none of the above work, you might want to pull the solenoid off the head, remove the solenoid filter and verify the piston moves freely.

Thats a basic troubleshoot for it.
If you go through all this and it still doesn't work its oil pressure (the pump) or wiring related. so check all the wires for vtec.

 

Thanks for your help...vtec solenoid wires apparently snapped...cleaned it then soldered together then reset ecu...wallah! Instant Vtec is back...

 

u have a bar sticker on a LS/Vtec?

 

passed the visual on a stock LS motor, then slapped a fully built lsvtec motor once I got the sticker...