I had another thread going that went off topic.

I want to know if it's possible that Vtec is not engaging and I have no CEL.

Has this happened to anyone, or will I get a CEL for <U>any/all</U> problems in relation to vtec not working.

 

ya its possible seens it ran off oil pressure have u checked that

 

From your old thread it sounds like you arent sure if vtec is working or not. If you have a 12v test light or something to test the voltage going to the vtec solinoid then you will know for sure if its crossing over or not. All you have to do is run a wire from the vtec solinoid to inside the car and then take it for a test drive and see if you get 12v to the wire at 4400 RPM.

 

Can you redline 2nd gear? If so, the VTEC is working.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Dogginator &raquo;</TD></TR><TR><TD CLASS="quote">Can you redline 2nd gear? If so, the VTEC is working.</TD></TR></TABLE>

If vtec wont engage, will I get a rev limiter or something? I think I can hit redline in 2nd, I'm going to try it out tonight.

 

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

If vtec wont engage, will I get a rev limiter or something? I think I can hit redline in 2nd, I'm going to try it out tonight.</TD></TR></TABLE>

The engine will simply fall on it's face near 6000 RPM, i.e. no power.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Dogginator &raquo;</TD></TR><TR><TD CLASS="quote">Can you redline 2nd gear? If so, the VTEC is working.</TD></TR></TABLE>
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Dogginator &raquo;</TD></TR><TR><TD CLASS="quote">

The engine will simply fall on it's face near 6000 RPM, i.e. no power.</TD></TR></TABLE>

I'm not to sure about that. My gutless B16 would make it to 8000 RPM in 4th gear and "pull" or "accelerate" just fine in fact it would get up there quick enough for me not to question if vtec was working or not untill a couple weeks later.

 

You will not make to redline with any oomph on the primary cam lobes.

 

i have a similar problem where my vtec solenoid keeps going bad.. (it went back acura replaced it and it went 2 weeks after it got replaced) it works most of the time but sometimes it wont and like dogginator said... <TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Dogginator &raquo;</TD></TR><TR><TD CLASS="quote">

The engine will simply fall on it's face near 6000 RPM, i.e. no power.</TD></TR></TABLE>

my car would rev limit at 6k but when it does work it'll go all the way up to redline

 

I hit a rev limiter at around 7k. Engine was at operating temp.

I can't crack tec!!

Haha jk, but seriously, I need to find a solution.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Dogginator &raquo;</TD></TR><TR><TD CLASS="quote">Can you redline 2nd gear? If so, the VTEC is working.</TD></TR></TABLE>
Hmm you learn something new everyday

 

Does the CEL work? It should illuminate when you turn the ignition to run with the engine off.

Is the ECU a stock USDM P72?

Have you check thet the screen on the VTEC solenoid is clean?

What are your symptoms besides not hearing or feeling the 4400 RPM crossover? Does your acceleration significantly decrease beyond 6000 RPM?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Dogginator &raquo;</TD></TR><TR><TD CLASS="quote">Does the CEL work? It should illuminate when you turn the ignition to run with the engine off.

Is the ECU a stock USDM P72?

Have you check thet the screen on the VTEC solenoid is clean?

What are your symptoms besides not hearing or feeling the 4400 RPM crossover? Does your acceleration significantly decrease beyond 6000 RPM?</TD></TR></TABLE>

My CEL definitely works, just had the o2 sensor code popping up with my new header/exhaust. I did the spark plug non foul fix and cleared the ECU, no more CEL.

The ECU is stock as far as I know, I haven't changed it. The car was bone stock when I bought it.

I have not checked the screen yet, I'm going to do it in the morning.

I would definitely say that it feels more like I'm "taxing" the engine after 5k rather than "revving" the engine. Almost like I'm over-exerting it, I hope that makes sense.

With the engine at operating temp, I could not get to redline in 2nd gear.

 

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

I have not checked the screen yet, I'm going to do it in the morning.

I would definitely say that it feels more like I'm "taxing" the engine after 5k rather than "revving" the engine. Almost like I'm over-exerting it, I hope that makes sense.

With the engine at operating temp, I could not get to redline in 2nd gear.</TD></TR></TABLE>

hmm i dont have mine in front of me so i cant tell if it would be much help to you but have you tried diagnosing it using the VTEC troubleshooting in a Helms manual?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by beastman@ &raquo;</TD></TR><TR><TD CLASS="quote">I hit a rev limiter at around 7k. Engine was at operating temp.

I can't crack tec!!

Haha jk, but seriously, I need to find a solution.</TD></TR></TABLE>

If you NEED vtec and have to have it there is a couple solutions. You can buy a cheap 12v 2 way switch that you can just switch on for vtec or for about 50-100 bucks you can get a RPM activated switch that will send 12v to the vtec solinoid. When you send 12v straight to the solinoid it bypasses anything the ecu tells it like the "temp" and "speed" check that it does before it will let vtec work. The only thing it wont bypass is the oil pressure because vtec needs that to switch over to the other lobes.

If sending 12v directly to the solinoid doesn't work, then you have a bad solinoid or you arent building up enough oil pressure.

 

I took off the vtec solenoid to check it out and possibly clean the screen. However, I can't find a screen. I figured it would be small, but I don't see one. I may have found my problem.

After taking off the solenoid I found the gasket that everyone mentioned, but no screen?


Here's the solenoid, no screen here either.


I was careful and slow when taking this off, I don't think anything fell out as I was lifting it off.

 

You need to remove the whole thing (part 12 is the gasket with the screen):

 

Just a hunch, but maybe your not fully engaging the gas pedal. Don't be scared if it touches the floor. Let it rip, and crack some tec already. Pedal position is of paramount importance

 

I'm pretty sure vtec will crackalack at any throttle position. I miss hitting vtec in 2nd gear at partial throttle and getting blank stares

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by neardon &raquo;</TD></TR><TR><TD CLASS="quote">I'm pretty sure vtec will crackalack at any throttle position.</TD></TR></TABLE>

This is true, although the engagement point can change. The 4400 RPM is for WOT.