Weird noise

Hey guys looking for help to figure out what this rumbling noise could be. I drove my 01' 3.4L TRD today and started to feel like something was not right. Kinda felt like the truck was being dragged down, like a loss of power. It kinda felt like it does when you press the breaks while pressing the gas pedal at the same time. Also felt like it took more from the engine to get the wheels turning. Then when I got home I heard a rumbling noise. Kinda sounded like a bad exhaust leak. I listened around the entire exahuast system but it sounded fine. I opened the hood and the engine sounds fine when it's in park. But when I put it in drive with the E Brake on, I walked around to the front and put my ear down by the front grill and could hear a rumbling sound. I could hear it best when my ear was close to the radiator. The engine still sounds fine when in drive but that's when I can hear the rumbling noise comming from somewhere infront of the engine, but not the engine it self. I do have really old and cracked belts that are being changed tomorrow. But I don't think old belts would cause this, or maybe they could, I don't know? The rumbling sound doesn't sound like a liquid or else I would think radiator. Any one heard this or have some similar instances before?

If I put my ear by the engine it sounds fine, I can hear the rumbling the loudest when my ear is in front by the Toyota emblem on the grill. Sounds like its comming from radiator or the fan. But again, it DOESNT sound like water or liquid bubbling, it sounds more like a rumbling.

HELP! I hate when my Tacoma isn't running perfectly!

 

Those clues are a bit puzzling, but my impulse is to say that your fan clutch may be broken and is not disengaging. Do you hear your fan during start and warmup, and then do you hear it go off shortly after? It does cause a little drag on the engine, but not that you would notice. And I don't think putting it into park or drive would affect it.

 

Haha I'm sorry, I know it's hard to help diagnose something when all I can tell you is what it sounds like, haha.

The fan is constantly turning I don't think I've ever seen it turn off. On the 1st generation 3.4 V6 the fan is connected to the water pump pulley. I don't see any wires or switches that would make it turn off and on. I think it's just a constant turning fan.

Does anyone think old cracked belts would make the engine work harder? Or make it feel like a slight drag on the engine? I did put some oil on the belts a couple days ago, actual gear oil to stop the squeaking. It was just a temporary fix until I can change them tomorrow.

 

It has a fluid coupling, and it will appear to spin even if not fully engaged, but it won't actually be driven by the engine (via the WP shaft) unless the extra airflow through the radiator is required for additional cooling. Again, I can't be sure this is your problem, but it is worth inspecting. Read this:

http://en.wikipedia.org/wiki/Fan_clutch

" A fan clutch can also fail in a stuck on position where engine power is lost even when the fan is not necessary. This type of failure can also decrease fuel economy."

 

Could be a bad pulley bearing? When you have your belts off to change them, rotate all of your pulleys by hand and see if any of them are dragging.

If everything feels good and the fan clutch checks out, I'd be inclined to think that you could have a caliper piston that's dragging. This would explain your felt loss of power.