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Old 08-25-2009, 06:43 PM   #1
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Default Running on 3cyl

So my car when started cold (even though its <90f out) now decides it wants to run really rough (what I'm guessing is 3cyl - sounds like subby, lotsa shaking, vacuum bouncing around). Once the car gets warmed up it runs fine. What in my tuning could be causing this?

msq attached and I'm going to attempt to datalog it in a few.
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File Type: msq msqtuneaug09.msq (35.0 KB, 46 views)
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Old 08-25-2009, 10:43 PM   #2
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hrmm I've had this on occasion I'd like to know as well, only on cold mornings then it won't for the rest of the day untill the next morning sometimes lol. I don't think it's tunning though IMO it's a bad ring..... IDK.....
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Old 08-25-2009, 11:03 PM   #3
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I mean I have 10k on this engine (rebuild) so I'd be mildly (understatement) pissed.
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Old 08-25-2009, 11:57 PM   #4
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check plugs, swap wires?
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Old 08-26-2009, 12:07 AM   #5
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check plugs, swap wires?
I'm on that tomorrow. I am just trying to think why it works fine once I start driving. Wondering if it has anything to do with my cold start settings.

My cranking pws are all fucked up I know.
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Old 08-26-2009, 12:12 AM   #6
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I'm running the base ms map settings (besides tune) from diy auto I wonder if I need to start tweaking ****..... but where to start....
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Old 08-26-2009, 10:15 AM   #7
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Originally Posted by naarleven View Post
I'm on that tomorrow. I am just trying to think why it works fine once I start driving. Wondering if it has anything to do with my cold start settings.

My cranking pws are all fucked up I know.
read the nuts loosening thread to learn about metal's ability to change shape when hot. all you need is a marginal contact somewhere that doesn't make contact when it's cold and when it warms up, does.

On my civic, I had similar issues. would run rough when cold and warm up and run fine. it got worse and worse over time and I finally dug into it and found one of the plug wires had come un crimped at the spark plug connector end.
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Old 08-26-2009, 11:19 AM   #8
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lower the fixed map value in your ASE settings.
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Old 08-26-2009, 11:30 AM   #9
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I was just fiddling with the fixed MAP value today, trying to remedy my bad cold starts. What is the theory behind it? I read the manual but didnt feel enlightened. The car starts, stutters and after 5 secs either catches on and purrs, or dies. Second attempt is always buttersmooth.

Stay safe

H.
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Old 08-26-2009, 11:32 AM   #10
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basically the MS fuels based on the MAP value you give it.

so if you have 80kPa in there, it fuels off your 80kPa row in whatever column your engine speed is at. Then it slowly decays back to your actually MAP value. If you're too rich itll run shitty for a few second before it levels out.
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Old 08-26-2009, 01:01 PM   #11
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Thanks. Its a pity you only get about two chances a day tops, to tune cold start. IŽll change it around and see what happens.

H.
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Old 08-26-2009, 02:36 PM   #12
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i adjusted my ve and spark tables today and it idles amazing!!! we'll c in the morning.
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