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Discussion Starter · #1 · (Edited)
I was fighting an issue where it would break up bad above 3000rpm and I didn't know why. I was logging the crank sensor and cam sensor in my Haltech and I noticed that during the ignition breaking up, I wasn't getting the consistent 24 crank pulses per 1 home signal. I still have no idea what changed, because it ran fine when I pulled the engine 5 years ago and I didn't change anything with respect to the crank or cam signals or sensors. But one thing I wanted to do was upgrade the cam sensor to a hall effect, so I drew up some flanges, had them laser cut in 6061 aluminum, and fitted a hall effect sensor. It absolutely solved my issue. If anyone needs one, shoot me a PM. I have 8 left.

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Hmm On most engines the cam sensor isn't used or dependent on the ignition timing ,

Most engines will run without the cam sensor plugged in.

I believe when you say crank trigger was causing misfire but I am wondering how and why you think messing with the cam sensor has anything to do with the crank sensor? Sounds like you played with the wiring while fooling around with the cam wires and moved the crank trigger away from some wire that was causing the issue.
 

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Discussion Starter · #3 ·
Hmm On most engines the cam sensor isn't used or dependent on the ignition timing ,

Most engines will run without the cam sensor plugged in.

I believe when you say crank trigger was causing misfire but I am wondering how and why you think messing with the cam sensor has anything to do with the crank sensor? Sounds like you played with the wiring while fooling around with the cam wires and moved the crank trigger away from some wire that was causing the issue.
Nope, not at all. The Haltech absolutely requires use of one of the two sensors, but not both. The factory sensor, which is a VR, creates a voltage, and in the Haltech table is a voltage threshold table which is RPM dependent. This basically tells the ECU when to consider the sensor being "made" as opposed to a hall-effect which is an unmistakable on/off square wave.
 

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What do you mean both? Crank trigger is always necessary, not "both". You can run any engine on crank trigger alone.

If you had dropping signal there are many reasons it could happen with a stand-alone. But would be difficult to reproduce on a factory computer. You neglected to mention you are using this with a Haltech ECU with definable inputs, as opposed to say, a Power FC.
 

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Discussion Starter · #5 ·
What do you mean both? Crank trigger is always necessary, not "both". You can run any engine on crank trigger alone.

If you had dropping signal there are many reasons it could happen with a stand-alone. But would be difficult to reproduce on a factory computer. You neglected to mention you are using this with a Haltech ECU with definable inputs, as opposed to say, a Power FC.
Original post states this is a Haltech. ;)

And yes, with a 12-tooth crank wheel (no missing teeth), you absolutely need a cam sensor to tell the ECU (factory or standalone) where TDC is. If you just have 12 pulses that are 30-degrees apart, and no other sensor, there is no way for the ECU to know what angle it's at.
 

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Had an issue with my haltech 2500 that would pick up cam sensor interference on the crank sensor.... i logged it doing this on the oscilloscope in NSP. It would cause the engine to lose sync at a given RPM depending on the predetermined voltages on the crank sensor. I have the issue outlined in my build thread and how i fixed it to work flawlessly on the oem toyota crank/cam sensors. Maybe its the same issue. Would be apparent if you posted a log of your oscilloscope.....
 

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Discussion Starter · #7 ·
Had an issue with my haltech 2500 that would pick up cam sensor interference on the crank sensor.... i logged it doing this on the oscilloscope in NSP. It would cause the engine to lose sync at a given RPM depending on the predetermined voltages on the crank sensor. I have the issue outlined in my build thread and how i fixed it to work flawlessly on the oem toyota crank/cam sensors. Maybe its the same issue. Would be apparent if you posted a log of your oscilloscope.....
I thought about that, but in the end, the hall-effect is the more robust sensor to use as there is no question with regard to threshold. Does it bother me that it was fine before I pulled the engine 5 years ago and now had an issue? Sure, but it's up and running on the hall-effect so it's no longer susceptible to magnetic drift. I put a hall-effect on the crank sensor probably 10 years ago and should've just done the cam sensor then. Oh well. :)
 

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Hello, as I know from my experience at wall work service the error will be back. Is the sensor reporting 0.5 deg advance when revving the engine ? if it isn't , it is bad( The grommet will be dry , knock it off towards the middle of the engine there is a 10mm bolt that holds the sensor in place , loosen it and use a magnetic tool to remove it completely. And be careful don't drop it in the timing belt section of the engine!
 

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Discussion Starter · #9 ·
Hello, as I know from my experience at wall work service the error will be back. Is the sensor reporting 0.5 deg advance when revving the engine ? if it isn't , it is bad( The grommet will be dry , knock it off towards the middle of the engine there is a 10mm bolt that holds the sensor in place , loosen it and use a magnetic tool to remove it completely. And be careful don't drop it in the timing belt section of the engine!
I'm not quite sure what you're saying. The O-ring on the sensor is fine and the cam sensors are nowhere near the timing components, but no, the issue is resolved. Thanks!
 

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I forgot the 2jz has that type of wheel for some reason I kept thinking of the LS reluctor. Clearly I've been in LS land too long. Sorry its a knee jerk reaction these days I guess 2jz are getting scarce or something.
 

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Discussion Starter · #11 ·
I forgot the 2jz has that type of wheel for some reason I kept thinking of the LS reluctor. Clearly I've been in LS land too long. Sorry its a knee jerk reaction these days I guess 2jz are getting scarce or something. But I am still wondering how your crank trigger dropping signal has anything to do with the cam signal.
Nothing wrong with that. Got my first LS-1 just over a month ago.
 

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Thats cool, I love all engines. Do alot of statistical analysis and many customers cars setting up for 25 years.
I learned that, so far, for swaps using the simplest and cheapest MPFI electronics (sequential overhead valve injection) with minimal bs (no active cam/dod/afl/etc...) there is a particular version of LS engine to acquire,
The LS engine to get for turbo is 05-07 L33 5.3L
That engine weighs around as much as a 2.0L sr20det and can easily produce 800-1000rwhp for 200,000 miles on stock bottom end, E85, stock ring gaps. They are going up in price and harder to find these days, soon like 2jz-gte and rb/sr will be very expensive. Heads up
 
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