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Trigger errors and Secondary injection issues


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Basics
Car-1990 Toyota Celica GT-Four
Motor-3S-GTE stroked to a 2.2 liter
ECU-Link Thunder
Injectors- 8x ID1700X
Current fuel-USA 93 octane pump gas
crank trigger-60-2 custom trigger
Ignition-IGN1A coils, Magecor wires, BKR8EIX plugs

OK lets start with trigger issues. I had issues when I 1st got the car started revving in neutral a 5000rpm.  Adam suggested I move my "head ground" away from the bolt that the star ground for the ECU is.  So I moved the head ground for the coils to a different bolt on the head and it has been solved till now.  I have been tuning and no issues but now that I have gone over 15psi I am now getting errors again with this higher load. Logs and tune supplied. 

Now for a little story that happened in-between the initial start and now.  As at one point I had moved the coil ground on the head with a temporary fix and that ground had broke.  I broke my ecu the 1st time I revved the motor over 4000rpm after it broke.  I didn't know there was an issue so I borrowed my friends ECU and put it in.  Broke his ECU just as fast with 1 high rev.  Sent both ECU's in and got them fixed.  While they were in I upgraded the coil ground wires to 12 awg wires and did nothing else.  Put the ECU back in and has worked perfectly since.  So the ground load from the coils with the clinder head ground broke was getting sent into the sensor ground of the coils and overloaded the ECU.

With that being said.  Thinking maybe just disconnecting Sensor ground for the coils and send the load elsewhere?  and if so where should I ground them?  Or see if that sensor ground is on the same pin as the crank sensor Sheild pin?

Fuel Issue now

So 10psi and 15psi have identical VE numbers as they should to get target Lambda.  Now when I hit 20psi the ECU has started transferring some of the fuel duty to the 2nd rail and when this happens I am leaner than the target lambda.  Telling my my injector data has to be incorrect.  How do I go about trying to fix this so VE remains the same like it should?

Badnews setup limiter mods lower EPW.pclr

My log is too big of a file.  How can I reduce the size?

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Ok. Target was .75 Lambda and when the 2nd rail came on I was hitting .81 Lambda.  So when the secondaries kick on I go 8% lean.

 

Looking at injector pulse widths I'm 6.50ms when just the primaries turn on and when the Secondary kicks in I'm 

Primaries = 5.40ms

Secondaries =1.10ms

(These are not including dead times)

Is there some kind of math to calculate how much pulse width I can add to the deadtimes to even this out?

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What I always do with staged injection is first set the staging table to all zero - so all fuel is then coming from primaries.  Hold it steady at medium load/RPM and adjust fuel table so lambda is sitting on target.  Then while still holding load/rpm, change staging table to all 100% - so all fuel is now coming from secondaries, if sec/pri flow ratio setting is correct then lambda will not change (there will be a flinch as you change over).  If lambda changes, adjust sec/pri flow ratio until it stays consistent regardless of which injectors are being used. 

For the trigger error, since it increases with load it would suggest it may be related to ignition noise getting into the trigger circuit.  I would definitely try moving that coil logic ground to somewhere else as a test.  I always thought the 3 grounds where isolated in those coils but the fact you fried the ecu when the primary ground was missing suggests they are not.    

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I went to try to make the 2nd rail do 100% of the fueling and I found I was on "Secondary Extra".  I then switched to "Sec/Pri flow ratio" and it was set to like 1.7 so I changed it to 1. Next I went back to 10psi and setup the secondaries to be 100% as soon as I hit 3psi.  I did a pull in the car and the Lambda was perfect.  I went back to where the 2 rails split the duty at 20psi and I needed 4% more fuel (fuel table should be 126 and needed 131) to get to the correct Lambda. Do I just live with a higher VE number or do you think I can solve this is playing with dead times?  The 3 logs with different pulse widths I did calculations from the pulse widths and found if I add .17ms to both dead time tables It will even out the flow transition. So going to at that and retune and try that out.

Still need to try the coil ground stuff.

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Yeah, I would try adding a bit of deadtime, I have had a couple of other users with ID1700X's before that needed higher than normal VE so I suspect the ID quoted  deadtimes arent perfect with the Link drivers (they test using old Motec M800's).  

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So tried and put the IGN1A logic ground to the same spot as the cylinder head ground and made no difference at all.  As soon as I get over 8500rpm I start getting trigger errors.  Any good ideas of things to try?  With a 60-2 crank trigger how high of a filter can I do and still be good revving in the 9,500 to 10,000rpm area?  I am still on filter #1.

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I dont think you will be able to run much more than filter level 2.  Can you do us a triggerscope at reasonably high RPM, say 6 or 7000.  

Assuming it is using a reluctor sensor - Is the missing tooth cutout on your trigger wheel "half depth" lik pic below? 

TZOwO7s.png

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My trigger wheelnisnhalf depth like that. My stuff was all from my previous Electromotive TEC3 ECU which is 60-2 only for trigger wheel option for that ECU and never had trigger issues.

I'll try and get a scope while I do a pull and the errors happen. Think going to a hall sensor would solve it?

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There is some regular noise coming through in the trigger signal.  It does cause the waveform to breifly cross the zero volt line in some places so the ecu would see this as an extra tooth and that would cause the error. 

In the 6000RPM scopes it is a bit intermittent but still visible.  In the 9000RPM scope it is quite regular, occurring around the same tooth every crank rotation.  It is about where the spark would occur for Cyl 2 & 3.  So I suspect this is still related to spark energy getting in somewhere.   Dont know why we dont see it for coil 1 & 4. 

The filter level 2 at 6000 didnt mask the noise by much - but it also didnt have a big effect on the general waveform either.  So you may be able to try level 3 filter.   

aQPmuGU.png

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@Adamw Do you think changing the crank tooth count would have any affect on the noise?  Is it because it happens to coincide with a tooth edge?  The coils are MSD's IGN1A coils (a lot more energy output than std IGN1As).  What about switching the trigger sensor to a hall effect?

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The tooth count wont have any effect except with a lower tooth count you could possibly increase the filter level to mask the noise.  With high tooth counts if you have the filter level too high you will actually filter out real teeth.  

 

6 hours ago, koracing said:

Is it because it happens to coincide with a tooth edge?

Anything that rises above the arming threshold and falls through zero is considered a tooth.  So in the scope above the event I have marked on the right would be ignored since it doesnt cross zero, but the one I have marked on the left goes up to about 10V, then the "noise" makes it suddenly drop to zero, then it goes back up to about 9V, then finally does the proper zero crossing to -20V.  So this goes above the arming threshold and crosses zero twice.  Its hard to see if it actually did cross zero in this case but it is close - if it did that would have been counted as an extra tooth.  When the ECU reaches the missing tooth and finds it has counted 59 teeth in the last rev rather than 58, it will through the error.  Zoomed and touched up pic below to show clearer that same left hand event in the scope two posts up.

bja3QW0.png

 

7 hours ago, koracing said:

What about switching the trigger sensor to a hall effect?

The "noise" appears to drop the trigger signal by about 10V, so I dont think a hall sensor will help.  There is more filtering in hall sensors, but in this case I think the noise is coming in after the sensor.  

I would probably try next a suppressor on the coil power wire, or you could try temporarily moving the main ecu ground to say battery or something.  Just something quick and rough as a test.  

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What about the possibility of having a variable crossing threshold for tooth count?  i.e. make it so that based on rpm one could use a negative voltage as the zero point to count teeth - at least in this case it seem like that may avoid this particular noise issue.

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That example I gave above was just one event.  There are other noise events in the scopes where the noise event is below or near the zero line.   

The zero crossing in our ECU's is fixed in hardware.  The reason is the only precise point in a VR waveform is the zero crossing (exact center of the tooth), any other point will vary in angular offset from the tooth center as the wheel speed changes.  Some ECU's do have an offsetable "zero" crossing for VR sensors, which does have a purpose in some special cases (such as when ecu is wired in parallel with a factory ecu which has a pull down or similar).  But I think for us it would cause more problems than it solves.   

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Just took the car out.  Filter at level 2 made the car miss fire earlier rpm and less boost.  decided to try filter #3 and could not even drive the car as in normal driving at like 3000 rpm it happened and showed 20,000 rpm.

Changed back to filter 1 and did a pull at 15psi with a scope at say 8,000+rpm and no misfire

leaving filter 1 tried 18psi and got the trigger errors again and that is the scope.  Not sure if the scope got an error or not.

What would you like me to try now?
(Just read the other responses. I will try moving the ECU grounds from the head to the battery next.)

If that doesn't work where can I purchase these "suppressors?"

What about adjusting my mag sensor for more air gap to bring the voltage down?

 

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Just tested the car with switching the ECU grounds straight to the battery and made no difference at all.  Next should I try the suppressor? Is the factory one ok or are there better ones to try? Watch video to see if I should use sensor ground or a chassis ground.

 

 

 

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I dont think the ground location will be too critical.  The general idea is you want the return back to the power source via the shortest route.  Most OEM's have the supressor grounded on the engine, but you could argue whether the source was actually the battery or Alternator when running at high load.    

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It might be worth trying a new set of shielded twisted pair wires to your crank sensor outside of your engine harness direct to the ecu just to see if there's any way something in the harness is inserting noise due to proximity.  Just as an experiment.

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Finally got time put the car back together and test it with the suppressor added.  Same thing happens.  Going to try using my extra shielded trigger wire from my flying lead harness and run the trigger wire outside of the main loom like I show in the video.
 

 

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Another update.  I tried running the trigger wires external from the main loom and again made no difference at all.  Then I thought my sensor side of the wiring runs near the alternator so I rerouted that since I had a longer ECU side of the cable and that also made no difference.  I still get errors as soon as I get around 8500rpm.

So here is everything done in order

1-moved IGN1A head ground away from ECU star ground point. (helped with errors in neutral at 5000rpm free revving)

This worked fine until under load (15psi+ of boost and 8000+rpm)

2-moved logic grounds on coils to head (did nothing)
3-Tried going to #2 and #3 trigger filters (made it worse)
3-Tried moving ECU grounds to Battery instead of head (did nothing)
4-add suppressor to coil power wires (did nothing)
5-rerouted trigger wires outside of main harness (did nothing)

Any ideas on what to try next? Or questions about my car to help if you see a possible issue?

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