2002 C5Z idle tuning help
05-13-2018, 10:22 AM
#1
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Thread Starter
2002 C5Z idle tuning help
I am a little stuck trying to get my idle dialed in after a cam swap, I am in the middle of speed density tuning and I keep entering reduced power from a P0106 map error code. I have tried adding air at idle, adjusting idle speed up and pulling a little timing from idle as well but nothing is changing. Currently my map sensor reads about 65 kpa at idle which is why I'm having these issues and nothing seems to affect this. Anyone else come across this or know a way to help with this?
05-14-2018, 09:32 PM
#3
Le Mans Master
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St. Jude Donor '13-'14-'15
1st of all when adding an aftermarket larger cam you need to ADD timing not remove it
Without knowing your cam's duration I would set the "base idle timing" both in gear and in P/N to at least 24* And then set both the high and low octane tables in the idle fuel areas to the same 24*( around .28 grams)
2nd if you Idle KPA is 65 then you need to raise ypur KPA Power Enrichment minimum to above that valve ( set it to like 75 KPA) Otherwise you may get false triggers into PE even if you are at P/T
If your engine is surging at idle it needs MORE idle airflow in the Desired Airflow table
If your MAP issue is a REAL code it needs to be sorted out as to why you are getting that code It may be a bad MAP sensor
However If you engine seems to be running fine then this code is what they cal a "false code" As mentioned above you can skew the MAP testing by maxing out the MAP rationality testing so the MAP will NOT be tested--But 1st make sure your MAP sensor is working properly------The only way to check the operation of yor MAP sensor is by data logginh it from idle to WOT--Being thst you know your idle MAP KPA I assume you have done this already Try my earlier suggestions
The stock PE MAP threshold is set at 55 KPA Like I said raise it to 75 EFILIVE table # is B3613
Without knowing your cam's duration I would set the "base idle timing" both in gear and in P/N to at least 24* And then set both the high and low octane tables in the idle fuel areas to the same 24*( around .28 grams)
2nd if you Idle KPA is 65 then you need to raise ypur KPA Power Enrichment minimum to above that valve ( set it to like 75 KPA) Otherwise you may get false triggers into PE even if you are at P/T
If your engine is surging at idle it needs MORE idle airflow in the Desired Airflow table
If your MAP issue is a REAL code it needs to be sorted out as to why you are getting that code It may be a bad MAP sensor
However If you engine seems to be running fine then this code is what they cal a "false code" As mentioned above you can skew the MAP testing by maxing out the MAP rationality testing so the MAP will NOT be tested--But 1st make sure your MAP sensor is working properly------The only way to check the operation of yor MAP sensor is by data logginh it from idle to WOT--Being thst you know your idle MAP KPA I assume you have done this already Try my earlier suggestions
The stock PE MAP threshold is set at 55 KPA Like I said raise it to 75 EFILIVE table # is B3613
05-20-2018, 04:44 PM
#4
Intermediate
If you have a wideband, use it and it will help out by a good margin. I increased my idle airflow until it read around 14.7 AFR, and increased timing until stable. Also, I would turn the A/C and both fans on and adjust with those running as well. Adjusting the fan #1/#2 air usage by a small amount will help, also. My cam is 20* more duration, +.1" lift more than stock and getting the idle/off throttle back to idle was the most time consuming to get correct.