Vtec hits hard and strong after first start up but after about 20-30 mins of driving vtec doesnt seem to hit at all or really weak. I jus recently got my oil done but when I shut my car off for a few seconds and restart VTEC hits hard again so im guess it has to do with pressure. shed some light anyone?

b16a p30 ecu

 

Vtec either works or it doesnt. There isn't anyway for it to hit HARDER or WEAKER. If it is actually feeling significantly different, it is probably something to do with the iat or ect calibration in the ecu itself that is adjusting the fuel/ign maps when fully warm in an undesired way.

 

Are you talking about the intensity of the sound?

 

my mistake guys

for clarification

VTEC works fines AFTER first start up but after 20-30 mins you dont hear the AGGRESSIVE crossover nor feel the SLIGHT power difference, so im guessin its not hitting or its weak. I kno when and how its supposed to sound given the proper RPM and it jus doesnt feel or sound the same after 30 mins of running time

My boy got an LS and wen my vtec doesnt crossover were side by side on the high way

BUT wen i shut my car off for a few seconds and let it coast then restart you CLEARLY hear the crossover at 6k

VTEC works its jus afterawhile I have to restart it or ill get walkd on by LS integra and its getting fustrating with having to restart the car on the highway jus for the vtec to really kick in.

I dont kno its jus weird

 

If youre on the highway and you downshift into your powerband than youre most likely going to be in VTEC so you wont hear the crossover.

What all do you have done?

 

bone stock with an intake and im talkin about upshifting into vtec

 

Try a different ECU, change your oil, check the solonoid wiring, and check the grounds.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by squeeks &raquo;</TD></TR><TR><TD CLASS="quote">bone stock with an intake and im talkin about upshifting into vtec</TD></TR></TABLE>

In a racing situation with a b16 especially youd probably only only get to the vtec crossover point once and thats if its from a low roll or a dig. Otherwise youd be in vtec the entire time youre racing.

But I dont think thats youre problem. Im guessing its either low oil pressure or an electrical problem.

 

VTEC = Increase in power?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by .Radical_Edward. &raquo;</TD></TR><TR><TD CLASS="quote">VTEC = Increase in power?

</TD></TR></TABLE>

??

OP: For VTEC to operate, the ECU needs to see:

-Coolant temp at operating temp (Via the CTS).
-Oil pressure
-VTEC hardware/software/wiring in good working order
-TPS reading above a certain throttle angle.
-Speed sensor reading above 15MPH

Are there any CELs on? Is all the above mentioned stuff in good working order?

VTEC operates or it does not operate. There's no middle ground. There may be intermittent operation, but that's also either on or off intermittently. It's a solenoid that forces a 3rd rocker into position so that the cams open the valves bigger. It's mechanical. Metal on metal. It's either operating or it's not.

 

check ur vtec solenoid for oil leaks

 

it wont kick in at first start up if its cold. it has to reach opperating temp first in order for it to kick in