Driveability

WHY DOES MY VEHICLE RUN BAD WITH MAF PLUGGED IN BUT RUNS GOOD WITH MAF UNPLUGGED?

NO MAF READING (0V)

•    Check MAF fuse. If fuse is good, check that the MAF you are using is

wired correctly for the harness you ordered.

WHY DOES MY VEHICLE RUN BAD WITH MAF PLUGGED IN BUT RUNS GOOD WITH MAF UNPLUGGED? 

DTC P0102 (LOW FREQUENCY MAF)

•    Check that MAF you are using is wired correctly for the harness you

ordered.

WHY DOES MY THROTTLE BODY NOT WORK?

•    GM drive by wire (DBW) systems require that components integral to the

system (Pedal, Throttle Body, Throttle Actuator Control Module (Gen III

applications only)) are matched to work together. This includes the

tune which must have the correct programming to match your throttle

components as well. If these steps are not followed a lack of throttle

response may ensue.

•    Check brake switch wiring.

•    Call PSI Tech Support with further

questions.

WHY DOES MY FUEL PUMP RELAY CONSTANTLY CLICK?

•    This relay is grounded in by the PCM wiring harness grounding lugs.

Check that the lugs are tightened the rear of the driver’s cylinder

head and that the surface on the engine is clean. Also ensure that the

battery, engine and vehicle are grounded properly. Reference the PSI

Engine Ground Diagram.

•    If Grounding checks out, contact PSI to

ensure that the tune is set for ‘Constant’ fuel pump signal and not

‘PWM’ signal.