Engine light won't turn off no matter what I do, how do I turn it off?

 

Fix the reason it's on then reset the faults

 

Pull the codes and find out why the light is on.
fordfuelinjection.com has instructions for pulling the codes and a listing of the various DTC codes.
regards
rikard

 

I've got a code reader and it's popping up the VAC and mass air, my truck is running fine

 

"Engine" light or "check engine" light? Truck has both.

 

Check engine

 

Code numbers?

 

This sequence popped up,
1-2-1-5-6-5-1-2-1-5-6-5-1-2-1-5-6-5-1-1-7-2-2-1-2-1-7-2-2-1-2

 

121=closed throttle voltage lower or higher than expected
565=canister purge circuit failure
172=HEGO shows system always lean
212=loss of IDM input to PCM or spout circuit grounded

 

DTC 121: Indicates the TPS sensor's rotational setting may be out of Self-Test range.

Possible causes:

-Binding throttle linkage
-TP sensor may not be seated properly (tightened down)
-Damaged TPS

Does throttle move freely and return to closed throttle position?

• Disconnect TPS, check for damaged or pushed out pins, corrosion, loose wires, etc. and rerun codes with TPS harness disconnected. Is DTC 122 present (Ignore all other DTCs)?
• If YES-Key On Engine Off-Measure voltage between VREF circuit and SIG RTN circuit while connected, backprobing wires with needles (Do not force multimeter leads into rubber boot as damage will occur.)
• Is voltage between 4-6 volts?
• If Yes-Replace TPS sensor
  
  Note: Test between (VREF) orange and (SIG RTN) green wires. The image below is testing between (SIG RTN) green and (GND) black wires and should be ignored for this test.
  
• Now test between (SIG RTN) green wire and (GND) black wire as depicted in image above.
  Is voltage approx. 1.0V?