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2jz trigger 2 cam polarity


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2jz vvti - Link ECU storm

Cant seem to get trigger 2 cam polarity working right...

 

Everything worked out of the box under the 1jz vvti trigger settings

locked at 10 degree btdc offset 200

trigger 2 offset 170

Starts and idles great but trigger 2 signal is inverted and possibly causing my rpm limit issues at 5k rpm

After switching the polarity to trigger 2  the signal is flipped in the right direction but the signal is all out of wack and can get it running.

Back story: after 1st RPM limit error we noticed cps sensor was out of range so replaced that with a new one. Also for good measure, reran shielded wiring from both crank and cam sensors back to ecu.

Waiting for new cam senor to arrive, just wanted to reach out for any advice. Thanks!

Here are some files to help

trigger scope_running great.jpg

cam switched.jpg

first pull rpm cut.llg

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In your 2nd triggerscope picture (bottom) the cam sensor is correct polarity but the crank sensor is wrong in both pics.  So it looks like you need to swap the +/- wires on the crank sensor.

In the 2nd pic the cam sensor is outputing very low voltage so you may also need to set the trig 2 arming threshold quite low in the zero and 1000RPM cells.  try 0.3V@0rpm and 0.5V@1000RPM.

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On 11/15/2018 at 10:20 PM, Adamw said:

In your 2nd triggerscope picture (bottom) the cam sensor is correct polarity but the crank sensor is wrong in both pics.  So it looks like you need to swap the +/- wires on the crank sensor.

In the 2nd pic the cam sensor is outputing very low voltage so you may also need to set the trig 2 arming threshold quite low in the zero and 1000RPM cells.  try 0.3V@0rpm and 0.5V@1000RPM.

Adam, mad genius you are. Not just on my issues but all the problem and issues you catch is simply invaluable. Had her on a true mustang dyno yesterday 420/412 with a small hx35 on gate pressure - 20 psi and ran out of injectors. tuning on e90 with flex tune - it did 377 hp pump gas. very happy! Great experience with Link thus far! excited for the next season, Thanks again!

 

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Adam i must be more dislexic than i thought , but the trigger 1 here looks correct to me , and trying to figure out why i read it wrong 

looks to me to rise from 0v to 1.3v then fall to -1.16v and return to 0v

do you actually read it at 1.3v and falling to 1.16v ?

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6 hours ago, Greg W said:

Adam i must be more dislexic than i thought , but the trigger 1 here looks correct to me , and trying to figure out why i read it wrong 

You are not alone, missing tooth trigger waveforms catch a lot of people out as they kind of look opposite to what is intuitive.  A quick way to pick correct polarity is the trace will be rising through the "gap".  The two above are falling through the gap.

The part that is important to the ECU is it triggers when a edge falls through the zero line. 

Below is a 24-2 triggerscope with the sensor wired correctly, I have marked the edges that fall through zero near the gap.  Notice the spacing between the pink edges on each side of the gap are about twice the width to the teeth preceding and following, this is our -2 teeth.

jGwvEKM.png

 

Now below is a 24-2 triggerscope from an engine with the sensor wired backwards.  Notice now if we look at the edges that fall through zero we now have an odd "tooth" in the middle of the gap - and the gap is no longer 2 teeth wide, its more like 1.5 teeth.  With a 24-2 wheel the ECU expects to see 22teeth per rev, however with the sensor wired backwards it will see 23 teeth per rev.  The ECU will freakout every time it sees this "extra" tooth.

ycZ9b9O.png

 

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