2005 GMC Yukon • V8 2WD Automatic • 72,000 miles

Why does vehicle have an intermittent***** when idle / stopped for a red light?
Richard R
July 7, 2011.

Do you have a check engine light on and when was last tune-up?

Could be caused by one of the following below

Oxygen sensor.
Catalytic converter.
Fuel injectors dirty/sticking.
Mass airflow sensor/Airflow meter.
Throttle position sensor.
Crankshaft position sensor
Knock sensor
Manifold absolute pressure sensor.
EGR Valve
Fuel pressure regulator leaking or defective fuel pump.
Fuel contamination.
Foul/defective spark plugs.
Open spark plug wires.
Ignition coil/Coil packs defective.
Incorrect ignition timing.
Cap and rotor.

Note: If it doesn't apply disregard it and keep testing.

Jul 7, 2011.
No check engine light and last tune up was done end of last summer.

Richard R
Jul 7, 2011.
Do what I've suggested and comeback with testing results

Jul 7, 2011.