2015 - 2017 Corvette Z06: Service Bulletin: #PIP5395B: Ticking Rattle Or Buzz Noise Heard The Best In The Passenger Compartment - (Mar 20, 2017)

#PIP5395B: Ticking Rattle Or Buzz Noise Heard The Best In The Passenger Compartment - (Mar 20, 2017)

Supersession Statement

This PI was superseded to update Recommendation/Instructions. Please discard PIP5395A.

The following diagnosis might be helpful if the vehicle exhibits the symptom(s) described in this PI.

Condition/Concern

A customer concern of rattle or ticking noise that is louder inside the vehicle than outside.

The noise may be picked up at the back of the left valve cover.

The noise may also sound like a lifter tick

This may also be called a fuel line buzz or ringing noise. 

Recommendation/Instructions

Listen to the fuel line connection at the left side of the engine.  

If the noise is heard best at the fuel line (this sound will be real loud with a stethoscope).

The fuel feed line between the high pressure fuel pump and chassis fuel line could be the cause allowing high pressure pulsation back to the low side of the fuel system. There is not a good way to test the check valve, the line will need to be replaced. 

On  pickups and SUVs, a vibration in the fuel line at the fuel tank may also be observed.

Reevaluate the concern.

There  are two different fuel line types  that contain this check valve and vary by model. 

The line above is the fuel feed pipe for Corvette, truck and SUV.

This line connects the chassis fuel line to the high pressure fuel pump. 

These pictures above shows the chassis fuel feed pipe for the LT4 supercharged ZL1 Camaro. 

On LT1 Camaro and LT4 CTS-V this line would have 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. 

Warranty Information

Labor Operation	Description	Labor Time
4026830	Fuel Feed Pipe Replacement	Use Published Labor Operation Time

Please follow this diagnostic or repair process thoroughly and complete each step. If the condition exhibited is resolved without completing every step, the remaining steps do not need to be performed.