Idle - Dies at stop, ok when rolling.
09-09-2008, 01:00 AM
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Idle - Dies at stop, ok when rolling. C6 Z06. HPTuners:
After 10-5 secs idle suddenly dies down then comes back up. Sometimes it dies completely. But if the car is ROLLING 2 mph it idles PERFECTLY. The closest table I find that differentiates idle from a stop and a rolling is OL & CL > LTFT Idle Cell > Enable VSS and Disable VSS which I set to 0 mph. I have been working on this for a month. Any tuners have any suggestions on tables to alter?
After 10-5 secs idle suddenly dies down then comes back up. Sometimes it dies completely. But if the car is ROLLING 2 mph it idles PERFECTLY. The closest table I find that differentiates idle from a stop and a rolling is OL & CL > LTFT Idle Cell > Enable VSS and Disable VSS which I set to 0 mph. I have been working on this for a month. Any tuners have any suggestions on tables to alter?
09-09-2008, 08:57 AM
#2
Sounds like commanded timing or an anticipated airflow problem. Check timing & anticipated airflow settings, as well as, timing & anticipated airflow modifier tables for IAT, ECT, airflow during idle, idle mode identified TPS position. Also, have a look @ your MAF table & make sure it is tuned correctly. Good-luck
09-10-2008, 08:50 PM
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Perhaps so. Parameters logged are all ok at "1" mph, and then switches completely at "0" mph, foot off the pedal all the time, going way lean, and dying every 10-15 sec.
Question is, what table switches this. I am looking all over for this switch - it may be in the BCM (and not accessable???)
Question is, what table switches this. I am looking all over for this switch - it may be in the BCM (and not accessable???)
09-11-2008, 06:43 AM
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It needs more running airflow at idle - it is getting the airflow it needs from the throttle cracker table (which shuts off at 1mph when stopping), but you don't have enough in the table that controls idle airflow while sitting still.
09-12-2008, 09:23 PM
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OK I increased the Final Idle Airflow until it didn't die anymore. (also tuned the MAF so the g/cyl was just right).
Now it idles at 1500, ignoring the Target Idle.
Since it's an LS7 I can't get at the throttle cracker table. I would love to make it think it was moving all the time.
Now it idles at 1500, ignoring the Target Idle.
Since it's an LS7 I can't get at the throttle cracker table. I would love to make it think it was moving all the time.
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09-13-2008, 01:59 PM
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Got it. MAF, etc did need some adjustments, I returned the FIAF to the previous adjusted tune. The key was in the min ETC settings, kind of like what the cracker does. Very perfect and wonderful result.
