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Trigger 2 noise

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Can anyone tell me if this noise on my cam sensor will cause misfire   and backfiring through exhaust and generally running like shit. its on a new windsor 5l setup running  8 coils. Engine starts easy.

sven ford 347 SCOPE.jpg

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You would want to set the trig 2 arming threshold so that it is above that noise level, but otherwise it looks quite usable, provided it doesnt get exponentially worse at higher RPM etc.

In that scope capture your trig 2 waveform is about 6V high and the noise is about 0.5V.  So if you set the arming threshold for that specific RPM to say 3V, then the ECU will ignore everything below 3V.  

Are you getting trigger errors reported or any other trigger error symptoms such as RPM jumping around?

What coils does it have?  Do you have ignitors?

If you want to attach a short log of it running and the tune file I will take a look.


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Ok, no signs of trigger error in your log but it wouldnt hurt to bump that trig 2 arming threshold up to something more relevant.

No other obvious signs of an issue in your log.

A couple of comments after looking at your tune:

  1. Are you 100% sure your engine is using the "351/HO" firing order?  I know from a previous case that some 5.0's use the older 289/302 firing order.
  2. Turn traction control off for now.  It is not interfering in the log but with the slip aim at zero, it is going to start cutting as soon as the wheels start to turn.
  3. Set fuel system type to FP sensor since you have one, it will mean your tune is going to change but it will make your VE more realistic, make tuning easier and give you an extra layer of safety if fuel pressure ever drops. 
  4. Looking at your Avatar - does this engine have ITB's?
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Many thanks Adam, the 5l engine has a 347 stroker kit, the firing order is 351  as per custom cam grind specs,  traction control noted. FP noted.

yes ITB's, 48mm, home made when I had a bit of spare time a few years ago,  will set the arming threshold in the morning and see what happens :)


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For ITB's NA you will want your fuel & Ignition table Y axis to be throttle position, with very fine breakpoints for the first 10% or so of throttle movement.  I will attach below a fuel and ign table from an ITB engine that will be better starting points.  You can right click on your existing fuel or ign table and chose import/export>import from file.

Next, air flow balance or sync is very important for decent low speed running with ITB's, have you checked airflow is well balanced with a synchrometer or stethoscope etc? I cant see in the photo if there is adjustment between the individual blades or not.

ITB Ignition Table 1.lte ITB with MAP comp Fuel Table 1.lte

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Also I noticed you dont have accel enrichment enabled.  You typically need plenty of this with ITB's.  

Looking through some of my files they seem to vary greatly, but below will be an average starting point.  I have some files with 3x this amount of enrichment...


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