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1999 GMC Suburban Repair Question


Topics covered: Engine, Sensor, Knock sensor.
Mileage: 133 miles.

Asked on December 22, 2010

Engine Ping

I have a 1999 GMC Suburban with 136,000 miles. 5.1 liter. The engine pings at idle or when I am accelerating or running on the highway. It seems some what intermittent. It not noticeable when the engine is cold. But when the engine warms up the knock or ping can be heard all the time. what is causing the Ping?
Avatar Asked by davecincy

Answer

Replied on December 26, 2010

Run a scan and check for a defective knock sensor, the ignition is constantly adjusted by the ECU the knock sensor picks up vibrations in the block from engine pre ignition (pinging) and sends a signal to the ECU for timing adjustment, this sensor may be faulty, start here.

mark (mhpautos)

Tiny Answered by mhpautos (expert)
26,913 answers provided