Motor is a d16y8 with a p28 ecu , recent oil change to 4 quarts and it used to activate nicely.But now it doesnt seem fast as it used to be so i added a vtec light for a bit to see if it is engaging , and it is BUT when i dont warm the car up and drive trough the rpms the light doesnt come on because the vtec isnt warmed up enough right? well it feels like my car is the same with or without vtec engaging . So what do yall think of this problem?

 

bump .

 

I don't see the problem... vtec doesn't activate when the car isn't warmed up. If the vtec light is turning on vtec is turning on. SOHC vtec isn't that powerful, so you probably won't notice much of a change.

 

ok, when vtec is not engaging ..it feels the same as when the vtec light is on(but not engaging?) and my solenoid clicks and all but when i drive to 4800 rpms i listen for changes in sound and performance,but when it hits 4900 rpms i cant seem to find the difference as when i first swaped the motor. so even tho the light comes on it feels as tho its not strong as it USED to be. I noticed that when ever i reach 5000-6000 rpms it sputturs and ****, then it gets smooth , this is only sometimes.

 

Check your timing. Has the engine had a recent tuneup?? Spark plugs, dizzy rotor? etc

 

Have you cleaned out the screen filter in the solenoid? Maybe it's dirty and not allowing enough oil pressure into the head.

 

I drove a friend's 97 EX coupe and I couldn't feel **** as far as the vtec goes...

if you want to feel a power band put a big *** snail that doesn't spool till 4500-5000 and you'll feel the kick.

 

more than likely it is engaging... if you run through the rpms when the engine is not warmed up to operating temp vtec will not work. why are you beating the car up before operating temp anyways... talk about asking for some wear and tear you don't need.

anyways you could try activating vtec at idle and see if it in fact working. I believe you just need to add a 12v constant to the vtec solenoid. can't remember which wire though.... been a bit since i've done it. if it activated it will usually stall the car or idle very rough.

can anyone clue in on the above as a way to test vtec?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 91civic &raquo;</TD></TR><TR><TD CLASS="quote">Check your timing. Has the engine had a recent tuneup?? Spark plugs, dizzy rotor? etc</TD></TR></TABLE>

yeah i messed with the timing belt is this my problem? i tried to set my timing by putting it on TDC and matching up the lines on the cam gear. But this could be my problem most likely huh.
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by manson &raquo;</TD></TR><TR><TD CLASS="quote">more than likely it is engaging... if you run through the rpms when the engine is not warmed up to operating temp vtec will not work. why are you beating the car up before operating temp anyways... talk about asking for some wear and tear you don't need.

anyways you could try activating vtec at idle and see if it in fact working. I believe you just need to add a 12v constant to the vtec solenoid. can't remember which wire though.... been a bit since i've done it. if it activated it will usually stall the car or idle very rough.

can anyone clue in on the above as a way to test vtec?</TD></TR></TABLE>

i beat on my car for diagnostics test . I wont be beating on it any time soon.

 

same thing happens to me i have a d16y5 and it feels like it never engaes, but i have boost so i dont care lol

 

Your y5 doesn't count

vtec-e y0

lol egizzle or whatever just did a mini me w/ a d16z6 block / y5 head lol it's pretty cool nice sound