Fuel Line Pulsation Sound

A rattle or ticking sound may be heard coming from the back of the left valve cover on some 2014-2017 Corvette, Silverado, Sierra; 2015-2017 Tahoe, Suburban, Yukon, Escalade; 2016-2017 CTS-V, and Camaro models equipped with the following engines: 6.2L (RPO LT4, LT1, L86); 5.3L (RPO L83); or 4.3L (RPO LV3) It may sound similar to a lifter ticking and may be louder inside the vehicle.


Listen to the fuel line connection at the left side of the engine. The fuel feed line between the high pressure fuel pump and chassis fuel line may be allowing high pressure pulsation back to the low side of the fuel system. If the sound is heard, the line will need to be replaced. On some trucks and SUVs, a vibration also may be observed in the fuel line at the fuel tank.


There are two different types of fuel lines that contain a check valve. The lines vary by model. Only one line should be used on Corvette, truck and SUV models. (Fig. 9) The line connects the chassis fuel line to the high pressure fuel pump. (Fig. 10)


Fig. 9


Fig. 10


– Thanks to David Rutkowski

Sensor Locations of Hands-Free Power Liftgates
Missing Connector Seals


  1. Refer to latest version of PIP5395 for more information. On LT1 Camaro and LT4 CTS-V models, the line has a jumper line with quick disconnects at both ends. One end will connect to the chassis line and the other to the high pressure pump feed line.

  2. “TWO different types of fuel lines…lines vary by model” “Only ONE line should be used on Corvette, truck and SUV models” Other line type should be used on CTS(LT4) and Camaro(LT1,LT4). Is it right or wrong?