Idle second equivalent of starting an engine

[iwilltry]

This stems from a recent thread (http://www.gassavers.org/showthread.php?t=4700) about how much fuel it takes to start an engine compared to idling. I was surprised by the number of opinions expressed there when no one has done what appears to me to be be a simple experiment for anyone with a scangauge:

* Warm engine to normal operating temp and turn engine off.
* Reset scangauge.
* At t=0 seconds start the engine and idle
* At t=10 seconds kill the engine
* At t=20 seconds start the engine and idle
* At t=30 seconds kill the engine
* Repeat for say 10 minutes (5 minutes of actual starting+idling and 5 minutes of engine off, with 30 starts in total).
* Record total fuel consumption from scangauge.
* Start engine and at t=0, reset scangauge.
* Record total fuel consumption of simply idling for 5 minutes.
* The difference between the two measurements, divided by the number of starts, is the additional fuel consumption per start.
* Divide this by the idling fuel consumption per second to determine the number of seconds of idling that is equivalent to starting the engine.

I don't have a scangauge (my car is pre '96). Does a scangauge have fine enough resolution to accurately detect the small difference in the amount of fuel consumed in this test? If so, can someone try this? I think everyone would be curious to see some hard results for different vehicles.

An alternative method would be to probe the injector during a single start with a program such as skewbe wrote to record the injector voltage through the audio input of a laptop. A small modification to the program could simply add up all the pulse widths during starting. This could be compared to the sum of pulse widths for the same duration of pure idling.

Some vehicles may have a separate "cold start injector" in the intake manifold. To ensure that this isn't supplying unmetered fuel during starting perhaps it should be disconnected (shouldn't be operating on a warm engine anyway).

Please don't let this thread turn into an exchange of opinions on whether killing the engine is a good or bad practice. Good or bad, I'm interested to see if anyone has determined the "idle second equivalent of starting" through actual experimentation on their particular vehicle. Thanks.