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Rough start everytime

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Old 03-11-2008, 04:27 PM
  #1  
telsonman
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Default Rough start everytime

Ok, so recently since its we've been having all of these cold fronts come it, my car has been starting up pretty rough. I'll crank it up, and it will idle between 400-1600 rpm's, just sitting there loping. It will drop to about 400 and sound like its about to quit(sometimes does) then it will shoot up to about 1600. It does this for about a minute or two then it usually levels out to about 900 assuming it doesn't cut off. I replaced the fuel filter today, and it has a new IAC on it and no smog stuff. Its weird that it only does it for a couple minutes, then everything is fine. My FP is set to about 38psi. After reading the searched stuff, it seems that it might be the ECT sensor. Would this be correct most likely???
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Old 03-11-2008, 07:15 PM
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Default RE: Rough start everytime

anyone???
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Old 03-11-2008, 07:35 PM
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mjr46
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Default RE: Rough start everytime

have you performed an induction cleaning lately to clean any carbon out of the intake and heads..carbon acts as a sponge and will absorb a/f until saturated enough where car will run normal again after a minute or two depending on severity of build up......= lean condition briefly
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Old 03-11-2008, 09:07 PM
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telsonman
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Default RE: Rough start everytime

The heads and intake haven't had more than 5k miles on them since I installed them, and they were clean when I put them on, so i'm thinking I can rule that out.
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Old 03-11-2008, 10:01 PM
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HACKGT350
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Default RE: Rough start everytime

could just be your car not liking the cold weather as the weather gets warmer and it goes away i just wouldnt worry about it
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Old 03-12-2008, 11:21 AM
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aode08
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Default RE: Rough start everytime

set your fuel pressure to 42psi,


set tps .99v key on engine off-green wire=positive lead
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Old 03-13-2008, 04:18 PM
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telsonman
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Default RE: Rough start everytime

Well, I put on a new ECT today and it did nothing. I'm still having the same problem. I bump the FP too. Still the same issue. I'm not sure what the problem is. I'm just ordered a OBD-1 code reader and I'm going to hook that up and see what it says. I'm also running rich as hell at idle for some reason. Its bad enough to wear it burns my eyes. I think my O2's are bad. When are you supposed to switch them out anyway(mileage)???
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Old 03-13-2008, 07:55 PM
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aode08
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Default RE: Rough start everytime

is the ground for the o2's ok? the ground opn the driver side head, that likes to break and get corroded
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Old 03-14-2008, 09:17 PM
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Jfsram
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Default RE: Rough start everytime

ORIGINAL: HACKGT350

could just be your car not liking the cold weather as the weather gets warmer and it goes away i just wouldnt worry about it
I have similar issues with my daily driven 93. Cold starts sounds like I have an aggressive cam.
Had the problem for a couple of years now. Plugs didn't help. I wanted to post the question for myself but answers like ^ really discourage that.
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Old 03-14-2008, 09:38 PM
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Default RE: Rough start everytime

might be your idle control valve or throttle position sensor
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