Do you think this works?? Anyone try this?

http://cgi.ebay.com/ebaymotors/MIvec...13392222QQrdZ1

 

Doubt it, it's made for the older MIVEC systems, but I couldn't say for sure. We'd need the exact details of how it works and the voltage levels of the signal our car uses to switch MIVEC on/off. I think the switch system for MIVEC in our cars is pretty basic - there's an oil pressure sensor, and when it hits a certain pressure, it sends a signal to the ECU to turn MIVEC on or off. If someone finds a way to replicate that signal, then we could control MIVEC.

I've been contemplating installing a switch so I can simply switch MIVEC on/off, but I wouldn't be able to change when it kicks on.

 

No, if i recall correctly, thats spec'd for some japaneese motors or something like that. Sorry I cant give you a really technical answer, the only thing im sure of is that it wont work.

 

I know their isnt one for our cars but on any of these types of controllers can you change the mivec/vtec kick-in seperate in each gear? probably not but i'd only find it helpful for me in first gear where i loose alot of power being an auto.

 

There are two criteria for turning on or off MIVEC. Engine RPM and oil pressure. Duplicating the signals to control the switchover point wouldn't be too hard (it's just battery voltage, on or off), but to get more than 1000rpm worth of adjustment, generating a false signal to fool the ECU would be more difficult.

The ECU looks for the oil pressure switch to be on or off by certain RPMs, and if it's not on or off as it's expected to be, it triggers the Service Engine Soon light.

 

Hrm, knew it couldn't be as easy as I thought. From what you say, though, my idea to install a switch should work just fine as far as shutting MIVEC off goes. I needed to invest in a code reader/reset thing anyways.

 

Pull out the oil pressure sensor.... = no mivec Another neat light on the gauge cluster too

 

This is one of the things that Haltech and RPW here in Autralia are working towards finalising very soon - it is a very interesting setup from what I understand but not impossible to achieve

 

The oil pressure switch operates opposite what you might think. It's closed at low pressure, and opens at high pressure. You'd need to wire in a switch with a second source of battery power. When the oil pressure switch opens and MIVEC kicks in, you need to supply that power again to get MIVEC to shut off again.

Also, with MIVEC disabled, you'll get a SES light if you exceed 4000rpm for more than two seconds, and I believe you're limited to 5000rpm because the ECU doesn't know what to do above that point without MIVEC engaged.

There's also a low limit check done when MIVEC is supposed to shut off. If you drop below 3000rpm for more than two seconds and MIVEC is still engaged, you'll get an SES light again.

Toggle switches could be made to work, but IMO it would really only be useful for long trips on the interstate, with the cruise set at about 80.

 

My commute is similar to yours. As things are now, I drive around going 70 all the time, when traffic flows at 80, plus time = money. What I'm hoping to do is to be able to switch MIVEC on/off from inside the car, and be able to enable it while the car is running, instead of having to jump out of the car, pop the hood, and reconnect the pressure sensor. It should work with just a regular toggle, though, without a second source of power. The idea is to have the switch work just like unplugging the sensor. I'm not sure, though, if the ECU will be able to handle the sensor suddenly coming back online.

I fear I may be hoping for too much.

 

Since the oil pressure switch is on/off maybe we can control the mivec with the tach signal. Something as simple as a small switch in the instrument cluster(not really what I would want to switch it on and off but a suggestion) Why can't we control it with the tach signal? (or use a small circuit to translate the tach signal voltage to a usable signal)