2004 Tundra 4.7 odd noise at 1800 rpm

Hello everyone, I have been here a few times in the past, and I recently picked up a 2004 Tundra Access cab 4x4 step side with the 4.7L V8 and 120K miles. It is in great shape, but I have one little issue I am trying to resolve. I will preface this by saying I have been turning wrenches for 40+ years, so I know my way around vehicles.

The issue is that when driving, and I hit 1800 RPMs on the gauge, there is a sound that sounds like pressure releasing and it will do it over and over while at 1800 RPMS. Now if you move just above or below that, it will stop. It also only seems to occur when the truck is in drive and moving. I did replace the PCV valve just in case, and have looked over the Evap Canister equipment. Now I have no replaced any of the evap canister equipment, as I wanted to see if anyone else has or had this issue. The only items I can think of that would make a pressure release sound like that would be the evap system, brake booster, or the PCV valve. It seems to be on the drivers side near the brake booster as best I can tell, but again it is hard for me to determine where the sound is coming from when I cannot replicate it in the driveway in neutral.

If anyone has any ideas, I welcome them, as it really is just annoying. It doesn't necessarily affect how the engine runs or how the truck drives. I can hear it and it is just something I want to fix.

Thanks
Jon

 

Check PCV hose? Even with a new valve.

 

Figured it out! It was a cracked heat shield that was resonating at 1800 rpm while driving. It sounded just like a pressure release! Bent the shields away from each other and the exhaust pipe…noise gone! Crazy!!!

posted in case anyone else runs into this issue in the future.

Jon

 

Jon,

I believe I have the same problem on my 2004 access cab. Where was the location of the shield you adjusted? -Adam

 

You may not get an answer, this member hasn't been active in months.

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I'm gonna take a wild stab and say he was talking about these heat shields, found between the manifolds and valve covers on each side of the engine, either the one circled in orange which I believe is separate from the manifold, or the one in red here which is I think attached to the manifold. But that's assuming you have a V8, you failed to include the one most important piece of info you could've shared - which engine you have. That, cab, year, and drivetrain are pretty important details.

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