trigger error

[Andrew Robertson]

Hi All,

running sequential on old-school SB Chev with 1 ignition drive firing an MSD box / single coil / distributor, G4 Extreme firmware 4.6.9.  Trig 1 is a MSD flying magnet crank trigger that gives 4 pulses per rev, trig 2 is an optical shutter wheel arrangement inside the distributor that gives 1 pulse per 720 crank degrees.  This set-up has been running strong for about 3 years.  Problem now is an intermittent miss that has been showing up increasingly under higher loads and RPM - sometimes feels like a very short complete engine cut.  When this happens, I get a burst of trig 1 errors - the count will jump about 4-8 at a time.

So a few questions:

1.  I assume that a problem downstream of the ignition drive (i.e. a problem with the MSD box, coil, cap/rotor, plug leads, or plugs) would NOT show up as a trig error, so I can safely assume the problem relates to triggering?

2.  What does a trig 1 error actually mean?  The crank trigger is trig 1 but these things are ultra-reliable - whereas trig 2 could well be the problem as I made that myself out of a gutted distributor and a modified unilite module.  Does trig 1 error basically mean there is a problem with the relationship between the two triggers seen by the ECU?

3.  When I first had the car running in a much earlier firmware version I used non-sequential batch mode, with 2 batches of 4 injectors, and simply used the crank trigger to drive it.  I have tried to go back to that now so I can determine whether trig 2 is the problem.  When I switch to multi-point batch mode I assumed trig 2 would disappear from the ignition menu and that I would simply have to enter a revised timing offset for trig 1 to get the car running?  The car will not start unless trig 2 stays configured as is.  How do I take it out of the equation to test it?  Why is it required in batch mode  - what am I doing wrong?

Thanks, Andrew

[Scott]

Hi Andrew,

'Trig 1 error counter' is a little misleading. The error count is affected by the relationship between Trig 1 and Trig 2, so a problem with Trig 2 could potentially cause the Trig1 error count to increase.

Interference from high energy ignition components could also cause a trigger error. The trigger cables should be shielded cable. It could be worth checking if your HT leads are breaking down.

To put your engine in group fire (non sequential batch mode) you need to do the following:

1) Go to trigger 2 in the ECU settings and change sync mode to none.

2) Go to Fuel Setup > Fuel main and set the injection mode to Multi-point group. Active drives will probably need to be set yo INJ1-8.

3) Remember to perform a store (F4).

Regards,

Scott.

[Scott]

Hi Andrew,

Thanks for posting an update. I will pass the information on about the batch-fire/trigger situation.

The older versions of PCLink are available on our website, so you could install one of these and downgrade your ECU firmware to enable you to go back to the way it used to be.

Regards,

Scott.