← Look into the faults of the GMC Yukon XL
Warning display
Reduced Engine Power: possible causes and documented repairs — 2000–2006 GMC Yukon XL
Of the records of the 2000–2006 GMC Yukon XL, 48 state “Reduced Engine Power” (Owner complaint: 42, Manufacturer communication: 6). The technical documents say how to deal with 2 of its possible causes. They are listed by the number of matching records, most first.
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Causes the technical documents say how to deal with (2)
Reduced Engine Power from throttle body connector crimp, broken wire or grounds
7 matching records
A vehicle may come in for a reduced power message and DTCs P0120, P0220, P1516, P2101 or P2135.
The TAC / throttle body codes may be caused by a loose wiring crimp at the throttle body connector or a broken throttle body circuit.
How to tell
What to do
- Inspect all related throttle body terminals for a loose wiring crimp.
- Wire breaks usually occur within 1 to 4 inches (= 25.4–101.6 mm) of the throttle body connector.
- On C/K trucks, complete SI procedures for voltage drop on grounds G103 and G104; grounds G103 or G104 may be loose or corroded.
- If a terminal crimp or broken wire is found, repair or replace only the circuits involved.
Throttle body carbon build-up: idle surge, reduced engine power, throttle DTCs (high mileage)
No matching record (stated by the technical documents)
As carbon builds up in the throttle body of a high-mileage vehicle, the ECM/PCM learns to compensate by increasing the throttle plate angle.
With enough carbon, idle surge, deceleration surge, tip-in hesitation, reduced engine power mode and/or DTCs may occur.
How to tell
What to do
- If SI diagnosis does not isolate the cause, inspect the throttle body bore and plate for obvious carbon build-up.
- If carbon is present, follow the Throttle Body Cleaning Procedure in SI.
- Depending on the vehicle, the idle learn reset/reset idle learn is normally found on the Tech 2 ECM menu for Module Set Up or Special Functions/TAC System.
- After ensuring that the throttle body bore and plate are clean, perform an idle learn reset/reset idle learn with the Tech 2/GDS and re-evaluate the concern.
Causes only records name
Not in the technical documents: named as the cause in records. A cause written in a complaint is the owner’s judgment or what a dealer said, not a confirmed fact.
Related symptoms, trouble codes and warning displays
What the technical documents state together with the faults above.
- Warning display
- Check engine / Service Engine Soon
Put together by FaultCrate from public records and technical documents. The cause and the repair are for the workshop to decide with the vehicle in front of it. Counts are records, not failure rates.