Thumping noise coming from intake

[2004LB7]

Only thing I can think of is the lash must have been adjusted wrong

 

[1FastBrick]

I would say, Oiling issue and or a miss adjustment of the valve lash.

I wonder if the ports in the rocker rails are plugged up.

 

[lexa]

Hi! Mine lb7 has the same sound from intake when cold. How can I determine which side of the engine should be disassembled ?

 

[2004LB7]

Hi! Mine lb7 has the same sound from intake when cold. How can I determine which side of the engine should be disassembled ?

Kinda a flip of the coin. You might be able to run the engine with the y bridge removed to see what side. But would be prudent to inspect both anyways