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Old 11-08-2012, 06:56 PM   #1
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Default Problems with cold starts

I just installed my MS2 over last weekend and it was starting just fine at first. Then a cold front came in and the ambient temperature dropped to the low 60's or high 50's in the morning. Now when I try to start the car for the first time or when I get out of work it takes a solid 8ish seconds of cranking for the car to fire. Once it turns over once it is perfectly fine and does not stumble so I know my ASE is good.

I know I have to make an adjustment to my cranking pulsewidth or priming pulsewidth tables but I am not sure how much to alter it.

Here are my tables currently:


Any suggestions would be appreciated.
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Last edited by Ryan_G; 11-08-2012 at 10:26 PM.
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Old 11-09-2012, 02:50 AM   #2
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Startup/Idle -> Cranking pulse.

You may need to either increase or decrease the cranking pulse for the injectors.

Start by taking a datalog from completely cold. Open the datalog and measure the time between when the crankig starts and the RPM passes 800rpm. This is your baseline, which you want to improve (email me that datalog).

Next day, increase the values in the cranking pulse table by 10% and datalog the start. If it gets better (again, measure like above), add another 5%. Repeat until you are comfortable with the result.

If it didn't get any better (or if it got worse), then remove the original 10% addition and instead remove 10%. If it gets better, keep removing in 5% steps etc.

This must be done once per day, in the morning, where the car has sat overnight, or if the car has been for more than 8-10 hours.
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Old 11-09-2012, 04:08 AM   #3
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I had to increase mine by about 15%.
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Old 11-09-2012, 04:16 AM   #4
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@Godless commie, please show you tables... - I am unsing the 725cc EV14 and I am also having a hard time starting the car if it is really cold outside...
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Old 11-09-2012, 04:33 AM   #5
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Here you go..

Please use it only with Dimitris's approval.
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Old 11-09-2012, 04:38 AM   #6
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Also, please note that my tables are in Celsius.
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Old 11-09-2012, 04:45 AM   #7
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Quote:
Originally Posted by Godless Commie View Post
Here you go..
Thanks... (It's only to compare with my tables and maybe get a hint in the right direction...

Quote:
Please use it only with Dimitris's approval.
I don't care about Dimitris approval, as long as he doesn't get my New Enhanced MS finished... (*joke*)

BTW - here are my Cranking and Priming tables - as you can see - I got WAY higher Cranking PW and WAY lower Priming PW... This did work o.k. with the old RX7 injectors, but not with the new EV14...



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Problems with cold starts-cranking_pw.jpg   Problems with cold starts-priming_pw.jpg  
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