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Question for 82 idle quality?

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Old 10-14-2013, 08:26 PM
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alconk
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Default Question for 82 idle quality?

When I first start the car it will run about 1100 RPM until the temp comes up then it settles into a nice idle but the way it does it is weird. If I come to a stop but take off fairly soon it only drops to around 850-900 and that will stay that way until I get stopped by a red light lets say. Then the idle settles down to around 600 or so but takes a good 20 seconds to do so and will stay that way intil it cools off then the cycle repeats. Is this normal? And if not how would you correct it?
Old 10-15-2013, 10:11 AM
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rmm82
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Just about every time my 82 idle gets weird, it's a vacuum leak. The other day my idle was bouncing around 900-1000 rpm consistently. I pulled off the air cleaner and checked every nut and bolt around the TBs and intake. I found both TBs with loose bolts. I tighten them down and the idle is back to 600.
Old 10-15-2013, 10:21 AM
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hugie82
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the ECM is taking info in and while its warming up, it's on an open loop mode. So that's pretty much normal until the 02 sensor heats up and goes to closed loop.
Old 10-15-2013, 12:49 PM
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Arkyvette
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My car has a definite stumble when changing loop modes. The idle after the change is better. The time to make the change depends on engine temp for me. I have it timed to the point where I know its going to change modes while driving past the funeral home down the street....lol. Fuel injection in its infancy.
Old 10-15-2013, 07:11 PM
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74 LS4-454
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As mentioned in other threads, the CFI does have its quirks, that is for sure. And most of the time it is vacuum related as stated above.
Depending on the outside temp determines what the high idle will be, I can go up to 1400 r's during initial start-up and I always sit in the driveway for about 3 minutes or so, until the engine warms up and the idle comes down. Doing it this way, I never have any stumbles or stalls, like when I first bought the 82. It almost like the engine is saying, "hey, I need some foreplay before I can operate"
I idle @ 600-650 r's in "D" and around 700 r's in "P", or "N".
Also the PO had told me that he had the CFI set-up by an old school mechanic who really understood the system, and the way it runs, I have no reason not to believe him.......
To answer your question, why don't you try the method that I use during initial start-up, (and I think "Arkyvette" does the same), just sit there for a few minutes and then see what happens...Tom

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