i dont belive my vtec is coming on @ 4400. but i do have the secondary butterfklies wired up, they do open at around 5800. i do not have any check engine lights. anyone know what could be wrong. would the secondaries work with out the primaries?

92 dx
95 motor and ecu

 

primaries always "work" there's no closing mechanism for them. ... if the secondaries are wired up correctly they'll close when you start the car and open up at 5500 regardless of throttle position. if the secondaries are closing you're not really going to feel vtec or even hear it for the most part.

try running the car with the secondaries disabled and see if you can feel/hear anything (pull vacuum line off and plug with screw). the car should feel like it's choking off up top if vtec isn't kicking in...

 

at around 5800 i can hear the secondaries. i just dont hear anything at 4400. im going to test some things today and see what i come up with.

 

is it possible for the computer to go bad. i did some testing with my friend. he got a 92 jdm b16 hatch with p30. when his vtec kicks in around i think 5800 its loud. we oput my p72 in his car and we barely heard vtec kick in like its doing in my car now. we then put his p30 ecu in my gsr hatch and you could hear the vtec a little better than with the p72. as of right now im looking for a p72 to test out with.

 

but when you get into the upper rpm range you can feel it can't you... and I think you proved that both vehicles/ecu's are working fine by swapping ecu's, vtec kicked in for both cars on both ecu's. it's just not as pronounced on the gsr. do a full throttle run with the car cold and then again when it's up to temp(hear/feel the difference).