So my friends bone stock 99prelude is having an issue.

One day, this problem just started for no reason...

The car acts like it has a rev limiter at 6k rpm. whether you sit at idle and just rev it, or while driving... rev limiter is at 6k

Checked the vtec solenoid, just unplugged it, and car has same issues (so it's not the problem of vtec engaging, and loosing oil pressure?)

checked limp mode? No codes are thrown, and we unplugged the battery and de-charged the car to erase the memory... Problem persist...

Any ideas

I'm stumped.

BONE STOCK 99 prelude.

 

Is your car at normal operating temp?
Is your temp sensor fucked?

 

Dose it cross over into vtec before the 6k limiter?

 

is it just ignition breakup by chance?

 

Distributor, cap distributor, rotor, spark plug, wire?