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Old 08-06-2008, 01:49 PM   #1
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Default Dies on a hot start

If it's nice and hot out and I've just driven the car upon restart it idles for a second and then the idle dips and then dies. This is with 550cc injectors. I guess it has something to do with the IAT sensor heat soaking while the car is off. What do i do about this? Maybe check the temps with the MS on but not the car and add more fuel to the AE at that temp?
edit: I forgot to add that if I keep my foot on the accelerator for about 10-20 sec I can keep it from dying, then when I take my foot off it'll idle again.

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Old 08-06-2008, 02:08 PM   #2
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go to coolant related air density. make sure it's set to AIT under advanced. Add % in the temps you are having issues.

that or your cranking PW values are bad.
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Old 08-06-2008, 02:13 PM   #3
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post start enrichment. add 5% and see if it still does it.
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Old 08-06-2008, 02:32 PM   #4
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pretty much what I figured. I'll try it after work and report back.
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Old 08-06-2008, 03:14 PM   #5
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I had the same problem with my car after I drove it and went to restart. It leaned out to the point of a stall. I didnt fiddle with the cranking pulsewidths because the car would start, and after a few minutes of driving the problem went away.

Follow Brain's instructions. I left the MSPNP correction table alone for the most part. I only corrected the bottom two temp readings and percentages.

120* w 101% correction
135* w/108% correction

Now the car starts right up when hot, no issue and idles at 15.2 or therabouts. Plus, I can immediately turn the A/C on.
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Old 08-06-2008, 03:21 PM   #6
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ok thanks, 15.2 sounds nice. I'm at ~12 with hi-res.
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Old 08-06-2008, 03:53 PM   #7
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Hi-res code is truly amazing stuff. Before Hires, after a heatsoak if I wasnt at 13:1 the car wouldnt even be driveable until the temps came down. Since changing to hi res and blindly scaling down my correction table, the car easily idles at 17:1 after heat soak and drives perfectly.

I'm still amazed at the improvement.
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Old 08-06-2008, 04:03 PM   #8
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I guess 460cc is a lot easier to control idle with. i still have a little fiddling to but I don't see how i'll be able to lean it out much further.
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Old 08-06-2008, 04:13 PM   #9
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I idle 460s at 110* intake temps perfectly smooth at 15.0:1
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Old 08-06-2008, 06:05 PM   #10
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I thought that the 96-97 MSPNP already had Hi-res in it? Only 90-93 and 94-95 could upgrade. Is that not the case?

Anyway, I don't have any issue with idle at all. It has taken me since April/May to get things to where they are now. I have an occasional fiddle here, fiddle there. I really could stand to go to a dyno, tune the cells, and get some timing back, but for now it is working ok.

Edit-I think I will just shut up now. I just noticed he has 94-95...
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