Rb25det Vvt Soleniod Dramas

[meatwagon]

hey i have searched and looked around for hours daily for the last few weeks and still cannot find what i am looking for,

the variable cam timing on the inlet cam of a rb25det has the electronice solenoid, it is two wire solenoid, seems to be a simple on off solenoid but what i am wanting to know is

1. does the ecu control this?

2. when does this get a power signal?

3. is the signal in response to rpm, oil pressure, tps signal, etc etc?

i just wanna know what triggers this and when

please help

[RB30-POWER]

on at 1050rpm off at 5700rpm, is the basic operation of the solonoid.

[Busky2k]

The ECU grounds the solenoid to make it activate in the stated RPM ranges. Its activated also on the basis of coolant temp (ie warm motor) and whether the motor is in gear or not (active only in gear) for the SR20DET so I'd assume the same for the RB25DET.

[RRob]

In the loom it's the blue wire with a white trace. Needs a 12v supply. Also powers the o2 sensor and idle control valve..

[WogsRus]

i disconnected mine for a while, a different car, it actually went better down low, but no go up top.

[meatwagon]

why would it have nothin up top if turned off at 5700 anyway

why does it not do it free revving????

and does it only do it when oil is hot??

[RB30-POWER]

If you go off this is might actually de-activate a little earlier at 4500rpm, 5700rpm for non-turbo models, either way up top its off.

http://www.tomei-p.co.jp/_2003web-catalogu...haft-specs.html

[WogsRus]

well for some reason, mine pulled way better down low, not sure why, eaven proven on the dyno, can't remember the exact figures though.

So is it turned on below 5000rpm or the other way arround?

[RB30-POWER]

[WogsRus]

that would make sence why most skylines have a big power lunge after 5500rpm. Nice, well anyway, mine might be stuffed, cos it certainly works in reverse, off, more torque down low, on lower torque more pull up top. Weird. Thanks mate that is some great info. Which manual is that from, and where can i get a copy?

[meatwagon]

now here is whats giving me a headache, i have a rb25det not in a r33 or r34 etc, running entirely off microtech, how can i get this solenoid to work when it should and to be off when it should????

[RB30-POWER]

the best thing to do is get a dyno run with the solonoid disconnected, then do another dyno run with it connected to a +12V supply.

then overlap the two graphs and look for the points that overlap, and program the microtech to switch it on/off at those points in the rev range with one of the outputs. (just use an rpm switched output, will depend on model microtech however)

[meatwagon]

well that was my thought, but will having it powered up constantly at 12v even at idle affect anything eg valves etc???

or can i just ramp it on and ramp it off?

[N I B]

I always do to power runs when tuning VVT engines (one of for whole rev range and one on) to find the best change over point with most basic RB25s needing 4700 rpm as of point but some heavy modded engines geting as high as 6000rpm.

Your aftermarket ECU needs to be able to ground its output for this valve and be able to turn on and of at any RPM and load,temp,TPS position etc.

[rbs30]

are you running a lt12?in your manual you will have a wiring diagram,it will tell you which wire you have to use for an aux output.more than likely it will be the plain white one for the vvt.run one side of the vvt solenoid to 12v and the other side to that aux wire,then setup when it needs to switch on and off in your aux setup screen in the ecu..also try the microtechefi.com technical forums.

[meatwagon]

yeh i am all over the microtech side of it, just wanted to make sure there would be no harm to the motor on or off at certain rpm's

all you guys have been really helpful, thankyou all