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Old 12-24-2006, 01:20 PM   #1
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Default Car idles rough when cold

when i start the car up, it idles at about 1200-1500 fluctuating for like 20 seconds, w/ vacuum @ about 19. Then it decides to behave, idle goes to about 1000, and vaccum to 21. Thoughts?
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Old 12-24-2006, 01:47 PM   #2
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year?
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Old 12-24-2006, 01:56 PM   #3
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IAC going bad. For some reason you have a temporary vacuum leak. Might even be the ISC thing on the bottom of your throttlebody. I was having a problem with that also, see if the ecu is throwing any codes.
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Old 12-24-2006, 03:45 PM   #4
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what size injectors?
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Old 12-24-2006, 08:14 PM   #5
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1.8s on a 91 with no engine management other than greddy setup.
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Old 12-25-2006, 02:13 PM   #6
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same setup as me...except a 90 not 91...and im having basically the same problem (1.8's here too)
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Old 12-25-2006, 03:18 PM   #7
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normal 1.6L ecu cold start hiccups....dont worry about it.
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Old 12-25-2006, 04:39 PM   #8
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I just got my wideband in and because of the enrichment mode, the damn thing runs at like 12:1 just idling, it dips down to 11.5:1, that could be what you are seeing also.
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Old 12-26-2006, 03:16 PM   #9
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Same thing I see with my 305s....Idles at around 12:1 and misses until it warms up a bit....typical if you are running large injectors.
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Old 12-28-2006, 01:19 PM   #10
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when I had the link on my car it took for ever to get the cold idle right. Either too high or too low. I would bet its a fuel issue
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Old 12-28-2006, 04:53 PM   #11
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Quote:
Originally Posted by Pitlab77 View Post
I would bet its a fuel issue
How so?
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