250

 

250hz

 

@codrus could you link me the caliper spreader you use? Tired of using screw drivers.

 

One caliper speculum:

https://www.amazon.com/dp/B005GLQCKA/

--Ian

 

Finally got a log of the misfire. Tach drops to 0. Engine slowly dies out.

 

Loosing power, the ecu even shows the voltage dropped.

 

New RX7 alternator arrives monday.

Voltage dropped after RPMs dropped though. If you look at the pictures the tach (driven off the coils) dropped to zero right before the RPMs dropped. So the coils stopped firing even though the ECU thought they were.

 

You have lag factors on the battery, it will always lag in the logs. Try turning on a heavy electrical load at idle, you'll see the RPM sag, MAP rise, and THEN the voltage drop.

Also try holding your car at the RPM you logged your car at here, and then unplug the power to your CAS and check the log. RPM will slowly drop to 0 again when it looses the signal. It won't instantly snap to 0 unless it looses sync, but if it just looses power, it will slowly drop to 0 as it "waits" for the next pulse.

I said this months ago, you're loosing power to something that powers your coils. Probably a bad main relay, or wiring to that relay or the coils. The fact that your batt voltage dropped suggest it's the relay.

 

I still say your coils are ****, the voltage not staying steady isn't helping things at all.

What's those lost sync count reasons, restarts? You aren't loosing anything other than coils? The coils are still powered by red/white off the main opening relay, same as the cas?

No cas loss, but cop loss? Dunno, but just my guess...

 

No loss of sync. Those are just from starting/restarting. Loss count stays the same the whole time.

I'll swap in a spare main relay and see if that helps. I'll aslo try the cas things.

 

unplugging cas.

Just realized my ABS computer is powered off the red and white wire that comes from the main relay. Going to try turning off ABS next time this happens.

 

 

Votlage drops slowly as expected, and you uplugged CAS so loss of sync immediately too as I mentioned.

Try doing same test, but pull the main relay instead of the CAS. Then the coils. See what that shows, see if it's same as log you posted when you caught the symptom.

 

Went to the dyno today. Went pretty well.

Only difference between these 2 runs was a 3" exhaust, 60psi base pressure (instead of 43.5), and about 10 track days and 10k street miles.

There is more spool to be found with better EBC tuning.

 

Also the misfire is like 5 times worse. LS coils will hopefully be in soon. And new alternator. Then we'll see what happens.

 

4 of these ordered: GM Coil Connector Kit For D585 D581 LS2 LS7
A bunch of D585's ordered.
1 SADFab bracket ordered. Specially prepared by sean.
1 SADFab coil wires ordered.

Alternator comes in tomorrow.

If none of this works im wiring 12v from the alternator to the coils to see if that fixes it.

 

Your problem sounds like a power-to-the-coils problem, not the coils themselves. I can't remember but I think you posted that you've tried other coils already in the past and it didn't fix it.

 

I agree. But i've been meaning to switch to LS coils. And its another variable to knock off the list.

 

FC alternator installed. The top bolt holes was stripped out of the box. So I nutted that bitch. Didn't have a chance to drice it tonight, but voltage is already better.



Ed and my car's plots.



Who knew that NASCAR turned both ways??



3 more days with my license. Then its gone for a month.

Going to a jewelry store tomorrow...fml

 

Car wouldn't start this morning. Was acting totally wonky. Battery showed good voltage. Car eventually wouldn't even turn on. Like no power at all.

Swapped main relay nothing.

Went to pull the main fuse (80 amp)

The side connected to the battery was screwed in by maybe 3 threads. Just loose and wiggling there. Tightened it up. Car started fine.

I dont want to jynx it but im hopeful this was the problem the whole time.