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Old 05-28-2010, 02:49 PM   #1
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Default prime pulse?

I was trying to improve my starting today and started tinkering with prime fuel.
I noticed that when I stall the engine (by unplugging the coilpack) and restart the car without turning the key all the way off (hence no prime fuel), the car starts almost instantly (like half to one cylce)
So, I assumed my prime fuel is too high and put zeros in all the corresponding boxes. This should remove prime fuel and I'd expect the same behaviour, thus instant starting.
This doesn't appear to be the case though. I still need at least 4 cycles before it starts, even with prime fuel off.
Is there anything else different between restarting without turning key off and a full start with key off?
I triead this at least 10 times and the result is very consistent.
Unplug ignition - kill engine - restart is instantly
Turn of engine with key - slow start
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Old 05-28-2010, 10:04 PM   #2
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I've probably got it backwards, but I'd expect pulling the coil would leave fuel in the cylinders. And that would suggest that removing fuel from the normal startup is the wrong thing to do.

I recently had start issues where it took too long to start up. I left the prime alone, as I believe it only pressurizes the lines up to the injectors, and I changed the pulse widths under "Cranking/Prime Table".
Try increasing the PW in the temp range you are experienceing by something like 0.3 and see if that helps. If not, try removing fuel by reducing the PW.
I like to take a screenshot or write down settings bofore changing them. It makes it easy to back up.
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