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Hello, I am working on a mustang 5.0 1995 with twin spark coil packs and 36-1 trigger wheel with Ford VR sensor and a Ford cam synch, 42 lb/hr injectors (for turbo app later). Installed DTA S100 ecu and set the crank sensor @ 300 ( since the sensor is 5 teeth ahead of the gap). The firing stroke is at tooth 4 and cam tooth is at 5 0r 6 (as per 2 oscilloscope readings I captured from the ECU).
As per calculations, I tried cam sensor position at 20 and -330 but the car doesn't start. Checked all wiring, no issues, checked all sensors, no problems.
From this oscilloscope, what would be the cam angle and injection angle?
Any feedback is greatly appreciated.
I took 2 readings, the first one shows the firing tooth.
I've been reading and thinking more about it, the new calculations I come across are crank @ 40 degrees and cam is at tooth 6 after gap so should be 60 AFTC or -290 BTDC.
Are these values correct? (confused about the crank since I have 15 degrees of ignition in the base map, so maybe it should be 35?)
I'm not familiar with the DTA ECU so I can't comment on the specific settings. The scope trace you've provided is too wide to really be able to see the pattern and I'm assuming this is what the ECU has decoded rather than the raw input as it doesn't appear to be a typical VR input? First up is the ECU achieving synchronisation? Are you seeing a consistent and sensible rpm during cranking (it appears you are from the rpm although it seems quite low at 150-160 rpm). Next i'd attach a timing light and actually see where the ECU is firing the ignition then adjust the offset until it's correct. The important aspect with a missing tooth + sync is to make sure the sync input isn't occurring near to the engine speed input or the ECU can get confused. There's various conflicting information on where the missing tooth should be located and within reason it's not that critical as the offset can be adjusted to account for it. Ideally it's nice to have it located somewhere around 60-90 deg BTDC #1.
Thanks Andre for the feedback. In fact, I purchased the timing light and a new battery that I will try today. I will check the timing and hope that the rpm will pick up better. The diagnostic display screen provides a message "synchronized, attempting to start" but no start cause no spark is occuring at the correct time.As per DTA manual, the firing tooth is the highest one that shows on the oscilloscope with all spark plugs removed except for cylinder one.My main ignition table starts with 15 degrees BTDC, which I think should be deducted from the crank sensor position. I will check it with the light and conclude the results.
Will keep you posted of the updates.
Hi Andre, Sorry for the late reply as I was busy with the tune :). I figured out that I am 20 degrees BTDC advance with the timing light and that helped me correct the trigger position. The car started, but too rich, spark plugs changed twice, I lowered the fuel, however, my injectors are 42 lb/hr bosch, which I am looking for their dead time. I did some search and found that these injectors provide a minimum PWM of 1.292 msec and 17 msec as max. Not sure if these values are correct. I am struggling with the idle valve settings too. The PID is currently off, and I am relying on the PWM table for the idle. The idle valve frequency is somewhere between 244-300 Hz (web search).
Do you have any data regarding mustang 5.0 HO? This car is a rebuilt engine for turbo installation, distributor deleted and coil packs installed. The problem is that I have no data about it since it is from junkyard (engine back to life :)