2002-2010 Trailblazer Envoy Rainier Ascender 4.2L I6 Mail Order Tuning

At Ewalt's Auto Tuning, we improve the performance of the 4.2L I6 engine, usually resulting in a boost of 10-14 horsepower and an increase of 1-3 miles per gallon. Our tuning also enhances throttle response, drivability, and acceleration. Additionally, if you need to tow, our tuning can assist with that too. We can accommodate most modifications you have, except for speedometer corrections and removing the rev limiter on 2002-2005 year models.

**Please note, 08+ Automatics will have a transmission control module also, if sending in your PCM please include this.**

We can adjust the tuning for any octane you prefer, but it is strongly suggested to use premium fuel. Many trucks may experience spark knock with the default settings. Opting for premium fuel will enhance both power and fuel efficiency.

Just some of the changes we can do:

• Fan 1 and 2 Temperature On and Off Change

• 90 second fan on at key-off (this feature activates when engine coolant is (Your Thermostat Temp) degrees or greater)

• Change transmission type (4L60e,4L80e, Manual or non-electric auto)

• Delete VATS

• Change Axle Ratio

• Change Tire Size

• Remove speed limiter

• Remove torque management - Torque abuse modes are modified to eliminate bog at launch

• Remove unused engine codes (Leave in notes what you need turned off)

• Emissions Removal For "NOT FOR STREET" rear O2, Cat, EVAP, EGR.

• Change Throttle body type: DBW or DBC

• Fueling modified for WOT (Wide Open Throttle) performance

• Timing modified for WOT performance

• Raised rev limiter

• Raised shift points

• Removes lag by changing downshift tables

• Transmission line pressure increased

• MAF calibration is year specific

• PE engagement adjusted to reduce KR

• Torque converter lockup tables modified to improve transmission life and eliminate converter lockup hunting

• Correct VIN number

• Enable E85 Flex Fuel

• V8 Swap