Put a B18C into a 96 Civic hatch. Vtec worked for about a week and since then I have had nothing I have been searching this site for about an hour trying to find someone with a similar problem but have not been able to find anything. I know the wiring is good to the solenoid and oil pressure sensor. The gauge cluster heat indicator is about 1/3 of the way up after running for hours. The oil is topped up. Every once and a while I will throw a CEL for speed sensor. I have replaced the speed sensor and still get the code. Weird thing is I have NEVER had a problem with the speedometer. What else is needed to make Vtec work? How can I test the Vtec solenoid and the Oil Pressure sensor?