VVTI 2jzgte Swap into Prado with R151 F 4WD Gearbox speed sensor problem

[2jPrado]

Hi, recently completed a 2jzgte swap from a 98 Aristo which was an auto car (jsz161) into a 90 series Prado.

Have been driving it around for a week and seems to go ok. i am having an issue with it at 5000rpm. It seems to have some sort of cutout, rev limit etc. From what i have read it is related to the speed sensor input SP+ SP- which uses a 2 wire speed sensor. I havnt connected it up to the cars speedometer as i am using the original 3 wire sensor to indicate speed.

I have made a square wave generator from a jaycar kit (20hz to 1khz) to mimic the sensor. As i dont have an oscilloscope i connected it to the original speedometer and used that as an indicator that it was generating a signal. What i found with this generator is that i could only get the speedometer to indicate steady between 100km and 160km.

I set this generator to a reading of 120km on the speedo and then removed it from my speedo and hooked it up to the speed sensor input. What i found was that the car could now rev past 5000rpm, but after that, the electronic throttle wouldnt work until i pressed the accelerator past the half way point. Went back again used the speedo to give a higher reading, this time 160km, removed it hooked it back on the speed sensor input but this time car would not go past 20km/h.


From what i understand the ECU needs to see a particular frequency and voltage in order to allow the car to go past 5000 rpm. Has anyone had any experience with this issue or some idea of what voltage and at what frequency the ECU would be looking for at a given speed. IE 600hz at 3 volts = 60km/ph and so on .

If i have these figures i might buy a portable velleman function generator and play around.

Any ideas to get past this 5k limit would be great.

[dumbass]

u got yr speed sensors confused
sp2+ sp2- should have a 4 pulse signal per rev of the output shaft and be 2 wires
this goes directly to the ecu

the 3 wire speed sensor goes up to the speedometer then signal goes from speedo back down to ecu to terminal called spd or sp1 pink wire or purplewhite wire
if your speedo reads correct then the signal to spd or sp1 should be ok

but u have to make sire u got a 4 pulse per rev of outputshaft on sp2+ sp2-

i stopped using the jaycar speedo correction units as to hard to get working perfect
i either use dakota digital ones or another type i buy from china which are very good

[dnegative]

Any ideas to get past this 5k limit would be great.

Neutral bypass, how are you doing it?
If you tell the ECU that you are in neutral all the time, you will have a 5000rpm limit.
Solution is to wire the neutral start to the clutch pedal or have a relay trigger it off the ignition switch (start)


Aristo's are pricks of things in swaps, mainly due to how the auto is so intertwined with the engine ECU.
9/10 mine will hit a rev limiter at 5500rpm under WOT due to TRC being deleted, dodgy the TPS so it never sees 100% TPS and its fine.

[dumbass]

forgot to ask y is sp2 not hooked up
i can understand not hooking up spd
did u have to mod the back of gbox and therefor u lost the sp2 sensor
this is common when have a 1uz auto and fit a transfer case to the back of it
well if this is the case do the job properly and fit the sensor in the transfer adpater plate

or u could fk off the jaycar unit and fit something with some quality
but u have to sit down and do some calculations to get correct pulses

u need to find if your 3 wire sensor is 20 or 4 pulse

i know the ratio from output shaft to speedo shaft rotation isaround 3 to 1
so on a 1uz box i know 3 rotaions of outputhsaft is one rotation of speedo shaft

and u need to get 4 pulses per rotaion of the output shaft on sp2+ wire and it needs to be sine wave

so if 3 wire sensor is 4 pulses u need to times that by 3 to get a rough 4 pulse to sp2
if your 3 wire sensor is 20 pulse then u need divide it by 12 to get roughloy 4 pulses to sp2+

its abit complicated unless u have played with speedo signals for 10 years hehehe

but i would try a better quality unit first

ive never had issues with any 1j2j vvti motor
the later oens are just a pain cause some have no 3 wire speed sensor on rear

[2jPrado]

Thanks guys, looks like i will have to try some of these things saturday and let u know how I go. I dont recall doing anything with the neutral start switch so i will check that and try to fool the TPS from seeing 100%.
Just to clarify i have a manual r151F gearbox (with a 2jzvvti) engine and it has a 3 wire speed sensor that goes to the dash and i have not hooked it up to SP2+ and SP2-. I believe the way the 98 aristo 2jgvvti auto ecu works is that it takes a 2 wire VSS into the ECU then outputs it for display to the dash Tach, instead of Tach first then ECU. So (corect me if im wrong and the other things dnegative spoke about dont work on my install) i need to generate a particular frequency to SP2+ and SP2- so the ECU thinks the car is moving in order to bypass this 5k limit.

[dumbass]

yes thinbk your right regarding sp2 input to ecu then ecu has output to dash or abs

just get a good signal box
convert the three wire square wave signal to a sine / inductive wave signal

u have to make sure the unit can do hi frequency as some cheap boxes run out of pulses

once u fit the box u need to put a scanner onto the vvti ecu and read road speed
keep adjusting it till the ecu road speed on the scanner is same as speed the car is doing
its fiddly work so just tkae your time
not sure if this will fix 5k limit as ive never run into that problem

[madmont]

I have a 1JZGEVVTI mated to a manual . ECU believes it is in neutral . No error codes except for 77 which does not set off the MIL . I used a few resistors to mimic the auto solenoids . No speed sensors connected to the ECU. Revs out to the speed limiter at 6300rpm. What error codes do you have?

[dumbass]

Hey mad
Are u sure tacho is accurate and defenately rev cutting at 6300
Are u just going of the factory tacho in the car
And does it do it in all gears
I never have had to fool ecu and join up neutral wires to tell ecu its in neutral
Or even run resistors to think its an auto When running manual box with auto ecu

[madmont]

Hey mad
Are u sure tacho is accurate and defenately rev cutting at 6300
Are u just going of the factory tacho in the car
And does it do it in all gears
I never have had to fool ecu and join up neutral wires to tell ecu its in neutral
Or even run resistors to think its an auto When running manual box with auto ecu

I would not swear to it being exactly 6300. I am using factory 6 cylinder tacho

I might rev it out in first and second but not in 3rd 4th and 5th
I use the resistors so the MIL does not activate

[2jPrado]

Tried the neutral start today, no difference in rev cut. (never had this connected originally car started and ran regardless) Joined the wires to simulate drive no difference in rev cut at 5k. Didnt get to try modding the signal to TPS yet. What i did find is that i hooked up a sine wave generator and put the frequency at about 600hz and the car revved past 5,500 rpm in first and second. Weird thing was got on freeway 1st flat to floor 6k rpm, 2nd 5.5rpm and third flat to the floor it wouldn't go past 4.5k rpm. What could be doing that ?? There are no other speed signals going to the ECU so why would RPM limit decrease as i shifted up gears. Running out of ideas. While im at it what is the correct way to connect M-REL pin.

[George]

convert the three wire square wave signal to a sine / inductive wave signal

all toyota ecu's I tried so far seem to run perfectly with square wave, as long as frequency is ok and ecu sees some current between sp2+/sp2- terminals (current value is used to test for sensor break)

newer toyota ecu's have flexplate slippage detection, that's why constant frequency won't work

[wilbo666]

Sp2 is a 12 tooth sensor on jzs161, not 4 tooth dumbass.

Also on jzs161 the speed signal is sent to the dash via the multiplex network, not an output from the engine ecu, etc.

Also I can confirm what dumbass says re a square wave input to SP2+ working, at least on jza80 vvti 2jzgte, as I fed in a 0 to 5v square wave and was able to get the correct output to the dash (jza80 auto engine ecus do output a signal that represents SP1 to the dash).



Cheers
Wilbo

[dumbass]

ok thanks for info wilbo

[woggin]

stock rev limit is 6,750rpm, its trivial but i thought id add it in.

this is very unusual because there are some factory aristos that do the 5k limit in neutral, and others, like mine that dont..mine will rev out to 7,500rpm (6,750rpm on the original ecu)..

its the neutral start switch, grounded car believes its in neutral/park, i.e startable...and once not grounded, able to rev out, but since u say youve already tried this id be looking at a different sensor...try a manual jza80 ecu, youll lose a/c control, because the jza uses a negative trigger as opposed to the jzs's positive trigger.

[wilbo666]

Woggin,

Manual JZA80 vvti 2jzgte engine ecus are pretty rare, he will have trouble finding one to try!

We are talking JZS161 here, not 147

Cheers
Wilbo