i have a 2000 civic si and it seems almost every time i get on it i hit the rev limiter at about 6000 rpms. i have plenty of oil and my car isnt cold. i also notice that it happens when i let my high cam switch back to my low cam without shifting. (for exmaple if im on the top of 3rd gear at about 7500 rpms and i let it wined down by just letting off the throttle untill vtec disengauges and my engine switchs back to the low cam.) i notice my check engine light turns on and i can no longer rev past 6000 untill i restart my car. i need help before i take my back to the dealership for service and pay an arm and a leg.

 

Wow, that sucks, it soundsl like your ecu is restraning you from going high rpm. Remember w/ vtec motors oil pressure is the key to high rpms, and vtec will not engage if you little or no oil pressure. I wouldn't be doggin it if i were you, try and figure out what engine codes you are getting. That could be a number of different things....

 

What mods have been done to the car?? Is the ECU the stock P2T??

And while VTEC won't engage if oil pressure is lacking, the engine will still rev higher. It will just sound like it's breaking up.

 

Seems like your probably throwing a code causing your ecu to go into protection mode....

I am guessing you probably have a loose/bad sensor or wire such as a knock or vtec oil pressure sensor etc...

I highly recommend you have some one check your codes once your car throws the cel to diagnose the issue.

To figure out how to check your cel, go to http://phearable.net and check out the tech section.

 

check the code and im sure that will answer your question

 

Well i have an intake, header, exhust, vafc, and a full suspention. other than that im pretty much stock. My vafc was installed professionally and is set at factory settings. i've been meaning to check what code its throwing but i wanted to see if anyone out there has had the same problem.

 

maybe the exust change the o2,who installed it

 

why is your vafc set to factory???? whats the point of having it?

 

It can control fuel as well as the VTEC engagement point.

 

yea i know what a vafc does and i did have it tuned at one point but, after my car started giving me problems i set everything back to factory.

FYI- i heard that if a car doesnt have any major work done to it (for example cams, bigger pistons, turbo, exc.), a vafc wont really help you to much.