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Old 12-29-2011, 05:34 AM   #1
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Default Cranking/startup questions (log and msq included)

Hi guys.

I actually meant to include a cold start as well but I accidentally did an overwrite of that log. Oh, well - it'll come later, so lets start with the warm startup:

Looking at the log, the thing that worries me the most is dwell. It's set to be 2.5ms both cranking and running (per TSE instructions) but is logged as 5.1 - 5.7ms during cranking and then settles at 2.5 when the engine is running. What's going on? Is there any danger of frying my coils?

Cranking RPM is set to 300 but only logs at around 180. It starts ok'ish when warm but rather reluctantly when cold (I'll do a log later). During cranking, the DIYPNP logs the voltage as dropping to around 9V, which I believe is too low. However, a voltmeter on the battery during cranking says something like 10.5V, which sounds more like it. Any ideas for improving the cranking RPM? Should I consider a new battery?

Cheers,
- Tom
Attached Files
File Type: msl 2011-12-29_08.34.18wamstart.msl (73.1 KB, 58 views)
File Type: msq 2011-12-29_10.31.37WarmStart.msq (83.8 KB, 58 views)
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Old 12-29-2011, 12:08 PM   #2
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A fresh battery is important, but also take a critical look at your battery cables. They are long, thin and have a tendency to fray.
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Old 12-29-2011, 12:18 PM   #3
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set cranking dwell to 5ms. the dwell increases as battery voltage drops.

but thats not the issue.
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Old 12-30-2011, 04:58 AM   #4
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Quote:
Originally Posted by Braineack View Post
set cranking dwell to 5ms. the dwell increases as battery voltage drops.
I have the TSE kit with the Toyota COP's. The instruction from TSE was to set them at 2.5ms for both cranking and running. Why would I want to set their dwell time even higher at cranking? I'm worried that the increased dwell at startup will damage them. But then again, it makes sense that they charge for longer when the voltage drops - but that long?

I've attached a cold start (4C / 40F). Of course it started up no worse than warm on the day I had the PC ready set up to log. Oh, well. I'll attach another when I log a more typical cold start. Either way, the logged cranking voltage and RPM are even lower - around 8 V and 110 - 140 RPM - and dwell time is even higher at around 6 - 7 ms.

- Tom
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File Type: msl 2011-12-29_08.34.18coldstart.msl (72.6 KB, 73 views)
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Old 12-30-2011, 05:05 AM   #5
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140rpm does seem a bit low. I would expect around 180rpm on a cold day.
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