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Old 09-12-2012, 01:35 AM   #1
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Default improving my startup

I am terribly noob, but I've noticed when my car is "cold starting" (granted it's not very cold around here yet...) but after it's sat a few hours or overnight, it has a terrible time starting. Usually it will turn and run for half a second and stall if I hit the gas. Also it likes to do half a crank and "freeze up"... but it will start like normal after a couple turns of the key.

I've been trying to find threads and topics about crank pulse and priming pulse etc... but I can't find anything that actually helps me understand what these are and how they work, so that I might play with them until the car starts better...

thanks for any help/explaination/tutoring....
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Old 09-12-2012, 02:11 AM   #2
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Dont hit the gas that soon?

Anyhow i'm running this VE for cranking fuel on my Adaptronic ecu.

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Old 09-12-2012, 02:58 AM   #3
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Although I'm not sure, and haven't been able to find out what that table is saying... Likewise with my crank pulse, prime pulse and other ignition genre charts...
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Old 09-12-2012, 03:16 AM   #4
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Fuel injected (in VE) per water temp in C.
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Old 09-12-2012, 04:37 AM   #5
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I'm game for answers as well.

Have you tried jumping it with another battery? Mine has the exact same issues and a very old battery. Ive been wonder if the starter, coils, etc aren't getting enough juice after it's sat for a while.
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Old 09-12-2012, 04:38 AM   #6
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And yeah, you have a similar table under warmup settings.
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Old 09-12-2012, 09:17 AM   #7
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Quote:
Originally Posted by imperfekt View Post
I am terribly noob, but I've noticed when my car is "cold starting" (granted it's not very cold around here yet...) but after it's sat a few hours or overnight, it has a terrible time starting. Usually it will turn and run for half a second and stall if I hit the gas. Also it likes to do half a crank and "freeze up"... but it will start like normal after a couple turns of the key.

I've been trying to find threads and topics about crank pulse and priming pulse etc... but I can't find anything that actually helps me understand what these are and how they work, so that I might play with them until the car starts better...

thanks for any help/explaination/tutoring....

So, tune your cranking pulse table?

Let me break it down very simply. Up means More, Down means Less.

It's plotted against CLT and pulses.

So at a given CLT temp you can inject more or less fuel during cranking.

so, drop the value really low at your temp that's given you issue, and crank. if it doesnt start, increase the number. Do it until the car starts.

Congratulations, you've learned how to tune.
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Old 09-12-2012, 01:57 PM   #8
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I have had starting issues for a while as well. I mostly understand the principals of tuning the MS under startup, which leads me to believe there may be another problem.

Has anyone toyed with the idea that the alternator circuit for the NB is a problem, since it tries to charge the battery while cranking? I tried starting my car without the Alt/WP belt and it seemed like it took a lot less fuel to start, but that is to be expected. Anyone experimented with an RPM based trigger using one of the outputs from the MS?

Also, I had a problem with alternator belt slip right after starting, that was non-existent with the OEM ECU. A new belt and some more tension solved it, but it kind of pointed to a lot of drag from the alternator.
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Old 09-12-2012, 02:05 PM   #9
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still shouldnt cause starting issues.
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Old 09-13-2012, 08:45 AM   #10
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Quote:
Originally Posted by 3rdCarMX5 View Post
I have had starting issues for a while as well. I mostly understand the principals of tuning the MS under startup, which leads me to believe there may be another problem.

Has anyone toyed with the idea that the alternator circuit for the NB is a problem, since it tries to charge the battery while cranking? I tried starting my car without the Alt/WP belt and it seemed like it took a lot less fuel to start, but that is to be expected. Anyone experimented with an RPM based trigger using one of the outputs from the MS?

Also, I had a problem with alternator belt slip right after starting, that was non-existent with the OEM ECU. A new belt and some more tension solved it, but it kind of pointed to a lot of drag from the alternator.
There is a thread somewhere (can't remember if it's mt.net or perhaps m.net) where this was discussed. Reverant offered to implement this adjustment for his customers but warned that it would relatively quickly leave them dead in the water if something happened to the rpm signal. I'm considering to ask for the fix since I both have hesitant cold starts and a squealing belt for a few seconds (neither happens with the OEM ECU).

- Tom
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