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-   -   Can't start diagnosis du jour... (https://www.miataturbo.net/megasquirt-18/cant-start-diagnosis-du-jour-89084/)

chitty chitty bang bang 05-21-2016 06:03 PM

Can't start diagnosis du jour...
 
6 Attachment(s)
96 1.8 miata turbo, batch fire, put in Trackspeed COPs. The car just cranks and does not start. I see RPM in Tunerstudio jumping between 0 and 300ish, but my tach does not move. The car just cranks with no ignition...

MSQ and Composite Log attached...

In Test Mode, injectors fire and plugs fire.

I've got the COPs set at 3.5 cranking and 2.5 nominal with 1.5 spark durations. Am I missing some other COP settings?

How can I tell if there is ignition during crank? How can i tell if there is fuel?
This can be either a setting issue or a hardware (PNP) issue.... suggestions?

aidandj 05-21-2016 06:51 PM


Originally Posted by chitty chitty bang bang (Post 1333326)
How can I tell if there is ignition during crank?

Do the plugs spark during cranking.


Originally Posted by chitty chitty bang bang (Post 1333326)
How can i tell if there is fuel?

Are the plugs wet

chitty chitty bang bang 05-21-2016 06:53 PM


Originally Posted by aidandj (Post 1333339)
Do the plugs spark during cranking.





Are the plugs wet

-

1 - don't have a test light and am only one person, what's the best way to tell? does not appear in composite log
2 - yes, but could also be from me firing the injectors in test mode...

stefanst 05-23-2016 10:27 AM

Your composite log shows that you're not synch-ing. This has nothing to do with the COPs. Without synch, MS won't even try to fire the coils.

chitty chitty bang bang 05-23-2016 10:57 AM

2 Attachment(s)

Originally Posted by stefanst (Post 1333575)
Your composite log shows that you're not synch-ing. This has nothing to do with the COPs. Without synch, MS won't even try to fire the coils.

I manually tested the CAS, rotating at 22.5 degree increments over a 720 degree rotation and am getting attached at the harness... I feel like something in the MS is preventing the signal from processing properly.

Recent PNP issues : C1 tantalum explosion, lost 5V supply. Replaced C1 and C2. Trace from D2 to C1 blown out, retraced with wire, replaced D2. C1 to U5 trace blew out, retraced with wire, replaced U5. Recovered 5V supply.

How can I diagnose the elements which process the OPTO and VR2 on the PNP?

stefanst 05-23-2016 11:47 AM

1 Attachment(s)
Your MS is getting a crank and a cam signal. It just can't- for some reason- figure them out. The crank signal on my '99 is just four quick spikes per 360deg/crank. Your signal has fully developed squares there, which does seem decidedly odd to me, but I have no experience with the pre-99 signals.https://www.miataturbo.net/attachmen...ine=1464018454

chitty chitty bang bang 05-25-2016 11:21 AM

8 Attachment(s)
Interesting - was it a change from on type of CAS to another for the NB?

Symptom:
The, car starts and kinda idles now. Matt suggested I up the Noise Filter for Primary to 25%. However, major Sync loss issues - about 20 in 4-5 minutes. More sync loss issues above 2000 RPMs so not really driveable. Note this is not a tune issue, but rather a signal issue. I cannot seem to find the error note in megalog view that details the reason for the sync loss.

Theory:
Believe something introducing electrical noise either Before or Within the PNP.

Actions:
Re-wired my Opto and VR jumpers and the 5V line and checked connections. - No Change
Tried upping the Primary Noise Filter up to 45% - No Change

Other symptom, may be related... or not...
Other electrical gremlin - my entire instrument panel's lights blink. Six times in 5 seconds, then off for about 3 seconds. Is this an OEM error message of some sort? Can't seem to find anything about it anywhere.


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