b16a vtec problem

i have a 90 civic si hatchback with a jdm b16a obd0. vtec will engage and then disappear very shortly after it engages. sometimes it wont even engage at all. as everyone knows who reads this my motor redlines at 8250 but since this problem it cuts off a little after 7000. well hope somebody knows what i am talking about.

Sounds like the wiring to the Vtec solenoid is loose or bad or the solenoid itself, could possibly even be a problem with the ECU itself.

not all b16as redline that high, you could have an ecu that has a redline at like 7200, i know my stock ecu for my b16 redlines at like 7200

not all b16as redline that high, you could have an ecu that has a redline at like 7200, i know my stock ecu for my b16 redlines at like 7200
no no it worked fine for almost a year redlining at 8250. all of a sudden my problem came up a few days ago.

oh then i guess it isn't the ecu

any codes ? check wiring, check oil level

any codes ? check wiring, check oil level
no codes, wiring is good, just changed my oil and it is good. it just is redlining at about 7000 every time. the vtec comes on only sometimes and when it does it disappears right after it engauges.