LS3 on Build - Idle Issues
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LS3 on Build - Idle Issues Good Morning - I have a new crate stock 6.2L LS3. I added a LSXr 102mm Drive By Wire Manifold to it. The ECU is from PSI, and the car will not idle correctly, When it gets up to temp it then just spikes and stays at 4200 rmp (on DTC code is the MAF). First Question: Should I use the standard LS3 MAF Sensor on the intake or an LSX MAF Sensor. Second Question: PSI is stating I need a custom tune due to the manifold type. I have an HP Tuner, so I would be able to custom tune if needed. So once I install the right MAF Sensor Type, I will need to learn what settings need to be changed for the manifold.
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From: Ann Arbor, MI
The 102mm TB is overkill for a stock LS3 and is difficult to idle tune.
You say "standard LS3 MAF" but there are variations. Please give us the part number and ideally a picture. If it came integrated with an air tube, you need to use that tube (almost certainly smaller than 102mm). If its a blade MAF, then it will fit many air tube setups, but definitely has to be tuned. (I recently learned that blade MAFs have a different connector/pinout than older style MAFs.)
I also think you will have to do all the airflow tuning.
You say "standard LS3 MAF" but there are variations. Please give us the part number and ideally a picture. If it came integrated with an air tube, you need to use that tube (almost certainly smaller than 102mm). If its a blade MAF, then it will fit many air tube setups, but definitely has to be tuned. (I recently learned that blade MAFs have a different connector/pinout than older style MAFs.)
I also think you will have to do all the airflow tuning.
