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Bitsyncmaster
06-09-2011, 01:17 PM
With this terrible heat we are having (upper 90s), I have noticed that the first start of my engine is not instant like it was when colder. A restart seems instant.

I copied what the OEM idle ECU does on engine start but it does not make an adjustment above 70 deg. F. So I put into my software to open the ISM a little more if above 70 deg. That made it worse. I then made the software start it with the ISM a little more closed and today that gave me an instant start. This is what the OEM unit does (cold open more and warmer open less) but it stopped making those changes above 70 deg.

So has anybody else seen harder starting on your first start of the day with these hot summer days?
DMC5180
06-09-2011, 02:17 PM
How much slower is it?
Bitsyncmaster
06-09-2011, 02:31 PM
How much slower is it?

It seems like a second or two whereas normally you just touch the key.

I'm not running the CSV so that may change what you see. I disconnected the CSV because it starts faster and does not need to clear the rich mixture on startup without it.

Note: The new software you have has this starting change in it.
David T
06-09-2011, 04:18 PM
When you start on a cold start you are starting on the fuel from the cold start valve. That means if the Thermo-Time switch is not just right and it's hot (like today) it is possible it will not open the CSV. You have no rest pressure so the fuel injectors are not squirting till the fuel pump can build up enough pressure to operate them. Try turning the key on and off once or twice and then trying to start the motor. It should start right up.
David Teitelbaum
DMC5180
06-09-2011, 07:18 PM
Same here, CSV disconnected, but it seems to be no more than a second if even that.
Bitsyncmaster
06-09-2011, 07:26 PM
Same here, CSV disconnected, but it seems to be no more than a second if even that.

Let me know if it's better with the new software. Mine just starts instantly at about 800 RPM and holds there. There is no fast idle at that setting above 70 deg. but it's not needed. Today was just one test so will have to see if it's always the same.