Fresh build on my 06 TBSS, stock MAF, ported throttle body, stock injectors, factory tbss intake, ported 243's stock stroke, .614/.621 227/235 @.050. Got a strange stumble while crusing down the highway. Checked the data log, when the stumble happens the "Mass Airflow Sensor State" goes to "MAP TPS Fail." The fuel trims go to hell, and then a few seconds later it goes back to "OK" and the trims come back. any info or insight would be helpful. Is it time to ditch the stock MAF?
post up tune and log
sorry that would be helpful lol
drivefromdyno.hplrebuildbasefinalairflow.hpt
it looks like the tune can use a little tlc on the fuel trims side at least. your pretty rich in the cruising section. Read up about maf tuning and ve/vve tuning. but what i would do first is go under engine diag - airflow and for test p0101,p0106,p0121 set min ect to 493 and test p0068 set enable rpm to 8k. Because of the mods your probably freaking out the ecms internally parameters for airflow correlation between the tb,map and maf. turn off cat test and post o2 test. those can command weird afrs whenever it wants to. thats under exhaust in engine diag and you still have some torque management still enabled (spark retard and torque loss %) under torque management - general
update - typo
Last edited by TCSS07; 05-10-2019 at 10:18 PM.
I will give it a shot! Thanks for the quick reply!!Originally Posted by TCSS07
i think your VE table is too fat and the computer is losing its mind as it moves from steady state (MAF) to transient (VE table) when you move the pedal. looks like the entire ve table multiplied by a percent, probably based on how much the MAF hz table was changed, overall from the dyno tune? not sure. Yah VE looks high, not sure. VE table shows change up to 8000 rpm, not sure how that change was made... how do you get it to spin to 8k when it cuts off at 7k with spark, fuel cutoff is disabled for some reason. I'm not an expert but your volumetric efficiency airflow reads 3-4 lb/min higher than what is actually coming in according to MAF sensor. Which to me means your VE is off, wayyy over. Its obviously in blended mode, using both MAF and VE but its fightin itself hard, just my observation. someone correct me as its late
TBSSs rule btw. love my black 07! good advice from TCSS07. im gonna go disable that damn cat and post O2 test on mine
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