High idle when coming to a stop?
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When I come up to a stop sign and I start slowing down I have about a 15-1700 rpm idle until I get completly stopped. How can I fix this problem? I have a 98 A4 H&C (228/228 588/588/112 comp with a 3600 TCI SSF. I have it idling good @ 850 (using LS1 Edit)but I can't fix this problem. Where are all the experts?
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People probably aren't giving you a detailed answer because we don't know to what extent your tune has been modified
You could do either of the following for a start:
1. Lower your Idle Air RAF table by 5%.
or
2. Lower your Throttle Follower Airflow Tables; Decay, Delay, and Decay in gear. Make your decrease in the mph or in the particular gear(s) where you experience the problem. Start with a decrease of 10%.
A search would have yielded all of the above and can give you some more insight into the various other idle tuning tables
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You could do either of the following for a start:
1. Lower your Idle Air RAF table by 5%.
or
2. Lower your Throttle Follower Airflow Tables; Decay, Delay, and Decay in gear. Make your decrease in the mph or in the particular gear(s) where you experience the problem. Start with a decrease of 10%.
A search would have yielded all of the above and can give you some more insight into the various other idle tuning tables
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how is it possible to have it come and go? mine will do it one day, and will then act fine the next. i can put it in neutral, rolling at about 10 mph, and it kicks the idle up to 1500, and sometimes i will shift into neutral when rolling it does not jump.
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Computer controlled EFI cars aren't like the good old days of carby engines - set the jet, idle screw and thats about it. If the tune is not right, it will do exactly what you are describing. Varying performance in different conditions. What you need is consistency. What you need is to re-examine your tune at idle and off-idle taking on board the advice already given.
Do you have the capability to tune it yourself? If so, look at running airflow, idle RPM, VE at idle and the throttle cracker/follower. Your answer lies in these small number of parameters.
Do you have the capability to tune it yourself? If so, look at running airflow, idle RPM, VE at idle and the throttle cracker/follower. Your answer lies in these small number of parameters.
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Originally Posted by one2run
how is it possible to have it come and go? mine will do it one day, and will then act fine the next. i can put it in neutral, rolling at about 10 mph, and it kicks the idle up to 1500, and sometimes i will shift into neutral when rolling it does not jump.