O2 sensors
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Joined: Sep 2013
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From: Cape Coral, Florida
Le Mans Master
Joined: Aug 2005
Posts: 5,375
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From: CA.
St. Jude Donor '13-'14-'15
Not working front 02's is always a problem with LT headers --That is why they are illegal in most states Because the front 02's are moved back with LT's from 2-3 ft and they are not made to read accurately that far back---Typically LT's will make your engine run RICH during P/T There is no 100% fix however a tuner can sort of trick the ECM into running a little leaner at P/T
A stock engine should have an 02 voltage AVERAGE between .450 and .550 millivolts
This will target your P/T fuel to be Stoich of 14.68-1
But with LT's the front voltage average will read anywhere from .600 to .700 RICH target---the larger the 02 average the richer the P/T fueling target is
A tuner can LOWER the 02 switching points to trick the ECM into a lower targer and end up close to 14.68 You will never get it back to 100% target of 14.68 but it will be close---
A stock engine should have an 02 voltage AVERAGE between .450 and .550 millivolts
This will target your P/T fuel to be Stoich of 14.68-1
But with LT's the front voltage average will read anywhere from .600 to .700 RICH target---the larger the 02 average the richer the P/T fueling target is
A tuner can LOWER the 02 switching points to trick the ECM into a lower targer and end up close to 14.68 You will never get it back to 100% target of 14.68 but it will be close---
