High sticking idle
07-26-2006, 10:37 AM
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High sticking idle I recently had a head and cam package installed on my car with a PCM for less tune (used ls1 edit). The tune is great, it idles good until you romp on it, the the idle wants to hang high. It wants to idle at 1400 rpm at a dead stop. Is it my tuning or a sensor bad?
07-26-2006, 03:28 PM
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just saw this on a FAQ in a tuner site:
Timing: This depends largely on the cam type. Cams in the 220 duration range can run well on 22-26* of timing, 230 range tend to run well 26-30* range and above that is trial and error as some cams may like 32* while others like 24*. See which helps your car idle the smoothest. I would recommend ADDING to the stock table and not altering the stock curve.
Take the car for a drive and check your idle. If the car goes on cruise control and the idle air is in a reasonable range (0.10-0.20 g/sec) you may need to slightly reduce the throttle cracker table. That table adds airflow while you are cruising and too much will keep the rpms from reducing.
Take the car for a drive and check your idle. If the car goes on cruise control and the idle air is in a reasonable range (0.10-0.20 g/sec) you may need to slightly reduce the throttle cracker table. That table adds airflow while you are cruising and too much will keep the rpms from reducing.
07-27-2006, 12:39 PM
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im having a similar problem with mine. Idles great, got the VE table dialed in, got the cracker table ZERO'd under 2200rpm and it still hangs around 1500 rpms, until I come to a complete stop. then it suddendly drops to where its supposed to be (idle routine kicks in). would increasing the decay rate help in this situation, even with the cracker being zero'd?
07-28-2006, 12:59 PM
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mine doesnt come back down unless i turn it off and restart it, then its idles dead on. It doesnt ever drop. However, i cant keep it running if i start it up with the air on. I have to start it up, let it idle and then turn on the air. It will still hang with the air on, just not as high, 1200 rpm.
08-07-2006, 08:46 AM
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I finally resolved mine by re-doing the base running airflow table. I guess the car needed some time to "learn" the idle after the cam install, and after some time had passed I relogged it, and adjusted the table accordingly using the (STIT + LTIT) data from a log file. No more idle hanging.
