Toyota 4AGE-VAST RPM input

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CHB
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Toyota 4AGE-VAST RPM input

Post by CHB »

I'm now currently building a Toyota with 4AGE 16V in it. previously the owner using stock ECU and runs a turbo in it.
I've made a connected between the stock harness to MS2 V3 board. I tried to crank it but no RPM signals was registered. I'm connecting the RPM thru the "NE" signal from the stock harness. any one have experience with stock Toyota 4AGE 16V ignition wiring?
Matt Cramer
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Re: Toyota 4AGE-VAST RPM input

Post by Matt Cramer »

Did you use a pull-up resistor on it? There's a guide to VAST here:

http://www.megamanual.com/ms2/vast.htm
CHB
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Re: Toyota 4AGE-VAST RPM input

Post by CHB »

my MS2 previously was getting signal from a "ignitor conditioner" and i've bypass D1 and D2. now should i still keep the bypass of D1 and D2 and run a 1Kohm to D9 as per instruction?
Matt Cramer
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Re: Toyota 4AGE-VAST RPM input

Post by Matt Cramer »

You got it.
CHB
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Re: Toyota 4AGE-VAST RPM input

Post by CHB »

i've checked the wiring and i found out that the signal from distributor does not goes to the ignitor, it was fed directly to 4AGE ECU "Ne" pin. this meaning that the "Ne" signal is not a 12V square pulse as per MegaManual VAST instruction. Could it be?
the car runs fine with stock ECU that this lead me into doubt how the wire-man does the job previously.
Matt Cramer
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Re: Toyota 4AGE-VAST RPM input

Post by Matt Cramer »

There were several ignitions used on 4AGEs; the VAST ones had the distributor signal wired to the ignitor. There was another design called ESA that wired the distributor signal straight to the ECU. An ESA system will have a 24 tooth wheel in the distributor while a VAST system will have a 4 tooth. Which distributor do you have?
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