ScubaSteveSi

The vtec doesn't kick in all the time when im driving and i have no idea why. It will work sometimes but then sometimes it doesn't. So if someone could please help me and let me know what might be wrong, that would be great!

B serious

iTrader: (1)

Vtec needs:

Coolant to be at normal operating temp (ECU has to see this electronically thru coolant temp sensor)

Oil pressure

VTEC and Pressure switch signal (duh)

Speed signal (car is moving ...ECU sees this via speed sensor)

RPM (duh)

n.famous.1

Start by changing the vtec solenoid.

B serious

iTrader: (1)

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by n.famous.1 &raquo;</TD></TR><TR><TD CLASS="quote">Start by changing the vtec solenoid.</TD></TR></TABLE>

lol...wtf?

Targa250R

Check your oil level. Make sure the car is sufficiently warmed to operating temperature. Do you have a Check Engine Light on?

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by n.famous.1 &raquo;</TD></TR><TR><TD CLASS="quote">Start by changing the vtec solenoid.</TD></TR></TABLE>
Um, no.

VTEC solenoids almost never go bad.

SI_Crazy218

Actually start by checking if the car has oil. Since the vtec solenoid is an electronically and hydraulic it needs oil pressure to work and if the engine does not have enough oil it won't work properly. Next u can check the vtec solenoid see if it's cloged

5_Lug_B

This is completely off topic but have you ever noticed that whenever there is a "VTEC isnt working" thread it is always a noob?

Now as B Serious previously stated:

Coolant to be at normal operating temp (ECU has to see this electronically thru coolant temp sensor)

Oil pressure

VTEC and Pressure switch signal (duh)

Speed signal (car is moving ...ECU sees this via speed sensor)

RPM (duh)

tx_ej8_49

Im with Si_Crazy on this one.
START BY CHECKING THE OIL FIRST.
No oil pressure...No vtec.

And the motor has to be at operating temp...moving...at the right RPM. Ive never seen a Vtec solinoid work sometimes and not work other times....

andoxviii

iTrader: (1)

Half of you sound like complete morons.

Just listen to B serious.

andoxviii

iTrader: (1)

You might also want to make sure your engine has vtec at all. Seeing as how you are new to the site you may have little to no knowledge.

What car do you drive?

sageuvagony

My vtak doesn't work either I thought all I needed was a sticker

5_Lug_B

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by sageuvagony &raquo;</TD></TR><TR><TD CLASS="quote">My vtak doesn't work either I thought all I needed was a sticker</TD></TR></TABLE>

Did you put it on both sides of the car? One time my friends DOHC VTEC got scratched on one side and it stopped working until he replaced the sticker.

JDM Boy

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 5_Lug_B &raquo;</TD></TR><TR><TD CLASS="quote">

Did you put it on both sides of the car? One time my friends DOHC VTEC got scratched on one side and it stopped working until he replaced the sticker.</TD></TR></TABLE>

LMFAO!!!!!!!!!!!!!!!!!!!! Veeeeery good one, thats was some funny **** lol!!!!!
But yea B serious is correct... in my noob times it didnt kick in... car warmed up a little... it kicked in but stopped at 7k in 3rd gear... hmmmm??? Gotta let her warm up some more, check oil blah blah B serious already stated the facts

usmc323

lol....

jdmjin

this happen to me once....i know its bad to even think of running the car with no oil.....most of the time when vtec doesnt kick in or it skips is because of the oil....which means that the oil is low!!!

crazyguy

do u have a check engine light on?because if u do..then maybe computer is protect the engine by shutting the vtec off

JDM Boy

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by crazyguy &raquo;</TD></TR><TR><TD CLASS="quote">do u have a check engine light on?because if u do..then maybe computer is protect the engine by shutting the vtec off
</TD></TR></TABLE>

Why would it do that? Oil purposes?

B serious

iTrader: (1)

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by JDM Boy &raquo;</TD></TR><TR><TD CLASS="quote">

Why would it do that? Oil purposes?</TD></TR></TABLE>

dude...cmon....wtf?

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by B serious &raquo;</TD></TR><TR><TD CLASS="quote">Vtec needs:

Coolant to be at normal operating temp (ECU has to see this electronically thru coolant temp sensor)

Oil pressure

VTEC and Pressure switch signal (duh)

Speed signal (car is moving ...ECU sees this via speed sensor)

RPM (duh)

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

it also needs the Solenoid to be in working condition....but they dont usually go bad.

peter-ek4

like everyone else said id check the oil but if dat doesnt work one of my mates had this problem b4 and it turned out to b a problem with a wire from his ecu.....he got his ecu chipped and one of the wire from it came loose and vtec only engaged sometimes till he got it fixed

yosh850

HEY IM A NUBE,SO HOW DO YOU KNOW THE VTECH IS WORKING?I HAVE A STOCK 1993 CIVIC SI(SO IT DOES HAVE VTECH)WHAT RPM DOES IT COME IN AT,IVE RAN THIS CAR OUT TO REDLINE,


,

HarfordCTR

Vtec!!!!!!

B serious

iTrader: (1)

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by yosh850 &raquo;</TD></TR><TR><TD CLASS="quote">HEY IM A NUBE,SO HOW DO YOU KNOW THE VTECH IS WORKING?I HAVE A STOCK 1993 CIVIC SI(SO IT DOES HAVE VTECH)WHAT RPM DOES IT COME IN AT,IVE RAN THIS CAR OUT TO REDLINE,


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

VTEC will come on at 4800 RPM. It will feel and sound like the apocalypse.

lol jk jk. You probably wont notice it in a SOHC like the D16Z6 (thats what you have). If you put an intake on the car (keep the exhaust quiet), put in in 2nd at like 3k rpm, floor it, and then listen intently for a change in pitch at 4800rpm.

darkwater_ghost

man I just read all the post thats some funny **** with the stickers, its be a while sence i've really worked on a honda, and I'm new to this site also, learn alot but dame whys every one diss on the new guys, some times the simplest problems havent been asked not relating to this vtec problem. but I just got my first ej8 and I dont know when my vtec kicks in but beeing stock I dont even want to take the rpm's that high.(5,ooo-redline) plus I dont ask alot of ouestions due to only 5 post a day.

JDM_Ej

I love these noob threads with guys that make one post and never login again.

civic j

i have the same problem, one day vtak hard, other days vtak not so hard,

changed my DOHC vtak stickers, no luck, had a oil change, yes same as,