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Old 06-04-2009, 03:11 PM   #1
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Default hard starting when warm

Im having trouble consistantly starting my car when its ran and coolant is over 170. Ive turned up the pw setting at 160 and it didnt effect it.

I just put new injectors in and did the req fuel and crank settings accordingly. It does idle fairly high, around 1600rpm. I figure i still need to fine tune some pw settings.

Does anyone know of a quick fix to this? I'd search more but Im stuck at work and i cant look thru forums too long. Was hoping to fix this before tonight so I could start tuning my fuel table some more, but 10min start ups can dampen that lol.
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Old 06-08-2009, 03:36 PM   #2
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The high idle issue might possibly be a vacuum leak around the injectors, cause that's what happened to me. As for the hard starting when warm issue, I also had the same problem. What I did to fix it was this...
Open Megatune and click on "Crank/WarmUp" then click on "Cranking Settings" Look where it shows the pulse widths, it should start at -40F mine is set at 9.0, and as it goes down and the temps get higher, the (mS) number should decrease. Mine at -40F is 9.0 at 40F it's 6.4 at 160F it's 4.0. I wish I could upload a screen shot, but I am on gay as dial up right now.
This may or may not fix your problem. It worked for me.
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Old 06-08-2009, 04:00 PM   #3
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search "coolant related air density"
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Old 06-08-2009, 07:47 PM   #4
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Im not too concerned with idle atm, havnt even played with the idle screw. Ill move it around before i have to pop the injectors out. O rings were fine before i put them in and theres no fuel leak.

Thx braineack, ill have to enable and get that setup right. That will more thsn likely fix the problem.

Going from iridium to a cooper sparkplug seemed to help a little too. My car was pinging from too hot of a plug, much better now.

Hope to get some dyno time within the next month .
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Old 06-13-2009, 02:29 AM   #5
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So i turned it on to corrected iat under coolant air density settings. Still having trouble getting it started.

iat just too hot, major heatsoak problems? shitty *** oem radiator?

The fans dont seem to come on when i turn the key over when its warm either. Figured the fans would come on around 195 degrees, but dont hear them :(.

What am i missing? I it set to one of the replies in the iat/coolant air density thread.
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Old 06-13-2009, 02:48 AM   #6
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What is your IAT and CLT temps before a hot start with just the ignition on?

What are your fan on, off temps set at?
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Old 06-13-2009, 04:46 PM   #7
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is your cranking table tuned for your injectors?
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Old 06-13-2009, 06:24 PM   #8
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Ill have to check the temps tonight.Ill check when the fans come in also.

Yes i redid the cranking pulse width settings according to the manual. I could post them up if that would help.

My car over heated today, ive got a bad radiator with a small crack, so im sure thats not helping the situation. My mishimoto comes in this thursday, going to have my car sit until then.
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Old 06-13-2009, 09:47 PM   #9
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If i had 550s with a 97 my cranking values would look something like this:

6.7
6.0
5.4
4.9
4.4
3.9
3.3
2.6
2.1
2.0
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Old 06-26-2009, 08:17 PM   #10
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thx again Braineack, your my #1 hero. either those settings or the much needed new radiator fixed the problem. it stubbles a bit, probly does 4-5 cranks and starts up.

idling high but haven't touched the idle screw......... still lol.

thx again!
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