MS sync loss reasons 31 and 32, already tried the normal stuff.
#1
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This issue has been plaguing me ever since I swapped this BP4W into my 94 chassis. Second hand DIYMS2 with the microsquirt module.
Around 5600-6500RPM, MS loses sync for reasons 31 and 32(loss of cam/crank signals). I've replaced both the cam and crank sensors with new units and units off of good cars multiple times. No change. All wiring rings good and I can not introduce this issue with vibration. Crank sensor spacing is within spec and doesn't change if adjusted in either direction. Sync loss is logged starting around the 46 second mark in the attached log. I have 20+ instances of sync loss in a quick 2-3 pull.
During some of my research to try and pinpoint this issue, I've run across people mentioning trimpots that can be adjusted in the MS that seem to deal with the cam/crank signals, but not where these pots are or how to adjust them.
Anyone know of these pots/procedure for adjusting them? Or have another suggestion that might be the cause of the issue?
E/ to add to the head scratching, it seems to do it more on a hot/already warmed engine. I.e, my outlap and most of first hotlap I have full RPM range. But then second lap the issue starts to show itself. That is to say, I'm not always hitting this hard revlimit. It only shows up intermittently, although more often then not.
Around 5600-6500RPM, MS loses sync for reasons 31 and 32(loss of cam/crank signals). I've replaced both the cam and crank sensors with new units and units off of good cars multiple times. No change. All wiring rings good and I can not introduce this issue with vibration. Crank sensor spacing is within spec and doesn't change if adjusted in either direction. Sync loss is logged starting around the 46 second mark in the attached log. I have 20+ instances of sync loss in a quick 2-3 pull.
During some of my research to try and pinpoint this issue, I've run across people mentioning trimpots that can be adjusted in the MS that seem to deal with the cam/crank signals, but not where these pots are or how to adjust them.
Anyone know of these pots/procedure for adjusting them? Or have another suggestion that might be the cause of the issue?
E/ to add to the head scratching, it seems to do it more on a hot/already warmed engine. I.e, my outlap and most of first hotlap I have full RPM range. But then second lap the issue starts to show itself. That is to say, I'm not always hitting this hard revlimit. It only shows up intermittently, although more often then not.
Last edited by Wingman703; 09-20-2019 at 06:42 AM.
#2
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I'll attempt to help since nobody else has come along. As far as where the trim pots are, I have no idea as I use ms3pro but here is a link that explains the process. If you open up your board you should be able to find it.
https://www.diyautotune.com/support/...megasquirt-vr/
Per others recommendations on this site you should be using ms3 with a 99+ engine, it's just a better system all around.
https://www.diyautotune.com/support/...megasquirt-vr/
Per others recommendations on this site you should be using ms3 with a 99+ engine, it's just a better system all around.
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