Engine noise 2004

Ok sorry if this has been asked before but I have a 04 tundra limited no oil leak but the water pump does leak. The engine makes an intermittent rattle like noise almost like when u attach a playing card to a bike spoke. It happens at different speeds but only when u accelerate. Noticed it the first time when we were reving the engine after doing one of the ac refill cans. It happens more frequent now. Any ideas??? Thank you
Kelly

 

Anyone??

 

The only thing I can think of is something making contact with your rad fan. Leaf? Stick?

 

Do you have a general idea of where the noise is coming from? How many miles on it? If it were my truck I would tackle the water pump first since it's leaking. If it has a lot of miles I would take care of the timing chain and tensioner also.

 

this^^^ and possible exhaust header cracked/leak (very common w 2004) which can sound like a rapid ticking noise

 

In the old days that noise meant possible broken motor mount. I don’t know how these motor mounts attach but maybe check it out.

 

I would just replace the obvious water pump and do the timing belt. The noise might be something else.....so take some fuel line hose and put one end to your ear and the other end you search around until you can pin point the noise.

 

I’m thinking cracked exhaust manifold as well.

Is it worse or better as the engine temperature changes?

 

My 05 has almost 200k miles on it and since about 150k it has had a slight knocking sound if I start it in cold weather and start driving right away without letting it warm up a little bit first. My dad’s 00 model with almost 300k does the same thing, and has done it for years, but only when it’s cold. He thinks it’s a cracked piston skirt, which sounds alarming, but he’s been doing this a lot longer than me. He says to just let it warm up for a few minutes before driving, which has worked for me thus far.

To me it sounds like maybe a gas knock or possibly the oil is too thick to reach an internal component in the valvetrain at first. I just tried using a thinner viscosity oil to test this theory, so I can let you know if that works because it’s still dropping below freezing here in Virginia.

 

Take a look underneath for loose exhaust heat shields and worn out hangers.

The 4.7's are just known for being noisy on a cold start, some claim piston slap others noisy injectors but there doesn't seem to be any adverse effects.

Mine gets 0w-20 in the winter and still rattles under 40 degrees. I just let it warm up for a minute and it's gone.

 

Most likely it's the exhaust manifold, I have the same issue, but I dont think it sounds like a knock. I highly doubt these engines would have a piston issue. The only way you can pinpoint the noise is with the hose, you can look all you want. I, being a mechanic have a stethoscope hooked to a hose. An exhaust manifold leak can sound like "A playing card on a Bicycle wheel"

 

Welcome! 1981 was a good year!