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Hello,
Question with my 97 EX, Even though the 1600 engine has great power for it's size, I don't feel any 'kick' of power at upper rpm's, ie getting on the freeway (have to wind it up in third) How do I know if the cam advance is operating correctly and at what Rpm is it activated? My Ign timing is right on and valves adjusted....

 
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How is your oil level?

If it's low it can keep VTEC from engaging.

 
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actually, low oil could trigger an engine malfunction code/light, so not likely.

if you really concerned, you could rig this:
https://www.civicforums.com/forums/1...tec-light.html

https://www.civicforums.com/forums/2...n-opinion.html

 
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Not low enough to trigger the light but low enough for the oil ports used for VTEC operation to not engage. Part of the the VTEC operation is from oil pressure.

My 94 Accord would do it to me when it was low. No VTEC, add oil

 
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Thanks all, I keep the oil full, Is there a set rpm the ecu engages the advance or is it load activated? is the valve on the side of the head for the oil supply to the advance actuators?
Been a Diesel mechanic most of my life... this engine is like a little toy to me

 
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VTEC selonoid could be clogged.

It is a set RPM and uses different feedbacks to engage. You can read the specifics of how it works online.

 
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Thanks!! And I was wondering why it does not have the upper end acceleration it did before? Duh... I pulled the front cover and checked timing belt tension and cam to crank timing as well as ignition timing......
I will check into it and follow up with an update!

 
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Well I ordered the Vtec gaskets, the unit has been leaking oil a little.
pulled the solenoid actuator off and opened it up, screen was clear. spool valve free, cleaned it all up, tested the pressure switch with air and ohm meter, contacts open under pressure. tested the solenoid with 12v and air, valve opens, blew through the ports in the head. re-installed unit. wired in a LEd to the ecu output and took it for a drive. Led lights at around 5500rpm and I can feel vtec working, but by then its hitting red line...
It seems like it used to come on way sooner like around 4000rpm where it would have better torque... Any suggestions???

 
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D16Y8 has VTEC switchover at 5600 RPM so your close!

https://en.m.wikipedia.org/wiki/Honda_D_engine#D16Y7

Not sure how to move it so it activates lower. Newer Civics it is done through engine management.

 
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Thanks a bunch! I know these engines like to rev, but with going on 250,000 miles, id like not to wrap it up to the top to get me on a busy freeway. I was thinking about a override push button switch on the shifter with a blocking diode to keep the 12v power back-feeding the ecu...

 
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Anyone have input on this? /\ /\

 
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Blocking diode is a good idea.

So you want the button to prevent VTEC from engaging?

 
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Sorry I didn't explain that correctly, I would like to manually kick on the vtec a little earlier say around 4500-5000rpm with a momentary toggle or push button switch. It would still be wired from the ecu, just would not feed back voltage from my 'override switch' to the ecu output... Muuhaaahaa (its alive!)

 
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I don't think that would work. The VTEC also uses hydraulic pressure to activate I don't think it is all voltage controlled. Maybe I am wrong but I don't think sending a signal to the ecu is all that needs to be done.