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HC92X Trigger noise oem Dizzy


VtrSp1

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@Adamw , i have do a new HC92X installation with Oem Dizzy on a HondaBseries Engine.

The car was  hard to start in the crank . I  do a triggerscope for  check the trigger voltage and after  i change the  Noise filter for cam and  crank from Level1  to Level 2. After this, the car start and run  great ready  for the dyno tune on  roller.

I  attach the calibration, trigger scope

From your experience, i need  to use the level 2 as filter because my sensor on dizzy are not good?

 

 

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Level 2 is common and fine for low tooth count triggers like the Honda.  But Im not convinced it would have much effect at cranking speed.  I would be more suspicious maybe your arming threshold is a little high, and when the engine is cranking slow the voltage from the trigger is not always exceeding the arming threshold.  

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@Adamw i have re-try this morning with level 1 on cam and crank and 0.2 V at 500 rpm as trigger level for cam and  crank anmd the car don't start.

I upload the old calibration and start at first crank

Attaached the calibration, the log after the car start and a trigger scope on cranking

 

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The cranking speed looks very uneven, does sound like it is cranking very slow?  It looks like as the piston comes up to TDC the cranks slows down so much that the ECU gives up waiting for the next tooth to arrive.  I have asked the firmware engineer to confirm if that is the case.  What battery voltage does the ECU report on cold cranking?   

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Ok, I just discussed with the firmware engineer.  It is not a cranking speed issue like I suspected.  It is a noise problem in this case.  It is seeing that small spike on trigger 2 as an extra tooth so resets the count.  If increasing the filtering level on trig 2 can get rid of this then that would be fine to do that.  

But if it still have problems starting with higher filter level then you will have to find the source of that noise.  Possibly rotor phasing, a weak ground or similar.  

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@Adamw ok thanks for the reply..

Today i have dynoed the car and i have a cut like a limiter at 8000 rpm but from the log there isn't the rpm limiter active.

The wideband lambda signal is lean because i haven't the output connected to the ecu, but from my wideband display the Afr is at 12 and from the log the fuel pressure is stable 

On the dyno I try with level filter 3 for see if help with the cut at 8000 rpm but nothing change 

i attach  a trigger scope with engine in load at 7500 rpm at the dyno..

From  the log  is a Fuel cut but it before the rpm limiter value...the noise from the dizzy activate the rpm limit random near the set point?
 

 

 

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Yes, my best guess is maybe a small spike in RPM triggered the RPM limit.  It was too short to be captured by PC logging at 40Hz.  

You could set up ECU logging with Engine speed, "limit flags word" and some other related channels logged at say 500Hz to confirm.  

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