Hey guys, I've been having some issues with VTEC engagement lately. I have checked the screens on the solonoid assembly, have enough oil, and I wired up a light to watch the point of engagement. Last night it was doing fine, engaging a 4800rpms, but today on the way to class I drop into second to go around somebody and I noticed it didnt engage until 5400rpms. I tried it a few more times at WOT and still, 5400rpms. Can anyone help me out with this? Thanks.

Oh yeah, its a d16z6.

 

How is the condition of your oil? Im thinking it may be dirty and not flowing as well which might me leading to the slower engagement.

Otherwise Im thinking the tach might be showing a different rpm then what you are expecting to see.

 

Full throttle 4800.
Partial throttle 5200.

Its possible your tach is off by a few rpms.

Your positive your hearing vtec right when it crosses over? Its pretty much only audible..i don't think your feeling it engage.

 

vtecwill engage from 4800-5200 depending on a few variables, such as IAT, coolant temp, oil pressure, and speed. I assume your tach is off.

 

I have a VTEC light, so I know it was engaging at 4800 last night, and 5500 today. I changed my oil yesterday. And I dont think my Tach got off 700rpms overnight. Something else I forgot to mention, my oilpan is dented pretty badly, could that affect engagement?

 

yes it can
vtec needs a certain amount of oil pressure and the dented pan could be affecting that

 

Anybody else have suggestions about why my x-over is varying in rpms?

 

Stock P28 engages at 5,500rpms. PERIOD. I can't imagine how we got some many responses and not on person seemed to catch this.

1). The light is gay. Remove it.
2). Its supposed to activate at 5,500rpms
3). The current draw from the light can and will mess with the activation
4). Why do you need to "see" when Vtec comes on anyways?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by d16vtecx &raquo;</TD></TR><TR><TD CLASS="quote">yes it can
vtec needs a certain amount of oil pressure and the dented pan could be affecting that</TD></TR></TABLE>

Did you bother to read the post? He says the pan is dented. A dented pan is NOT going to effect oil pressure. Pressure is controlled by the pump, not the shape of the pan. Unless he has a dent that has physically smashed the pickup and caused a restriction, this is not his problem. If you DID dent the pan that much, I assure you it wouldn't hold oil in the first place.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Hybrid93Eg &raquo;</TD></TR><TR><TD CLASS="quote">Stock P28 engages at 5,500rpms. PERIOD. I can't imagine how we got some many responses and not on person seemed to catch this.

1). The light is gay. Remove it.
2). Its supposed to activate at 5,500rpms
3). The current draw from the light can and will mess with the activation
4). Why do you need to "see" when Vtec comes on anyways?</TD></TR></TABLE>

Um, its not your car, so eat me. I will leave the light in, and it will be the end of the world And VTEC engages at 4800-5000. For some reason it was acting strange, but I drove it again and its fine. Y8 engages at 5500, z6 is at 4800, PERIOD. That is unless you are at partial throttle, then its at 5500. Why have the VTEC light? For no other reason than to prove you wrong.

Thanks for the advice though.

 

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

Um, its not your car, so eat me. I will leave the light in, and it will be the end of the world And VTEC engages at 4800-5000. For some reason it was acting strange, but I drove it again and its fine. Y8 engages at 5500, z6 is at 4800, PERIOD. That is unless you are at partial throttle, then its at 5500. Why have the VTEC light? For no other reason than to prove you wrong.

Thanks for the advice though.</TD></TR></TABLE>

Interesting considering I have a stock P28 rom open in front of me and it CLEARLY shows the activation point at 5,500rpms. But hey, it makes total sense that the ECU would magically change its activation point on you and now its acting fine.

You're light hasn't proved anything except your "passion" for flashy things that serve no real world purpose.

"Look, the light came on! Hold on man, we are about to propel ourselves into the next galaxy!"

 

sorry I havent had time to reply to your post, I was returning from the romulan galaxy 9. Okay, this car has a bone stock ECU. I bought it from an old man. It has always engaged at 4800, I had a straight pipe on it at one time when my resonator rusted through and it was loud as hell. And dont tell me it doesnt change the sound because its a single cam. It does, it sounded like my friends ITR with ITB's.
Recently it's been acting up though, VTEC hasnt been engaging at all, or engaging late in the RPM's. I dont know why, but it has. BTW, did the p28 your looking at come off of a Y8 engine? If so, there is you answer. Y8's are set to engage at 5500 no matter what.

 

maybe its your tps? or cus its winter? or a different oil filter?

i know, im just stabbing in the dark