2005 4.0-liter 1GR-FE V6 Vibration at 2200RPM

I have a 2005 Tacoma with 235,000 miles on it and have started noticing a vibration coming from the engine at around 2200 RPM. I first started noticing this while driving, so I thought that maybe the tires were out of balance. Had them checked and they were fine. So, I decided to see if the engine would also vibrate while park, so I rev'ed up the motor to 2200 RPM and sure enough, you can feel a distinct vibration coming through the steering wheel right around 2200 RPM, which tells me it's not anything in the drivetrain.

From searching the web, it seems like this is not uncommon, but most people are complaining about a vibration at highway speeds and not with the truck in park. I recently had the water pump go out, so while I was at it, I replaced the spark plugs, mass air flow sensor, idler pulley, water hoses and the drive belt. I also cleaned the throttle body and injectors and the vibration is still there.

Anyone else having their same problem?

 

This is a long shot, but years ago I changed plugs on a Ford and a few weeks later it started running like crap. It turns out one of the new plugs was bad.

 

Another long shot, but check that you haven't lost a piece of your cooling fan. I had it happen once on a '77 Camaro. Of course, that car was a piece of shit.

 

Make sure the engine oil is not overfilled.
Harmonic balancer may be coming apart.

 

Maybe not the most likely cause - but I would also look at the motor mounts.

 

I had exactly this happen on my 1998 Tacoma 3.4L. A small chunk missing from the tip of one blade. New fan fixed it.

I am chasing a similar vibration/hum as OP except at a lower RPM. Mine occurs at idle through about 1500 RPM and increases in intensity with any load from the drive belts, such as turning on lights (alternator), turning steering wheel slightly (power steering pump) or engaging AC compressor, but only after engine is hot. No vibration when cold. Checked all idler bearings, fan bracket and fan clutch. Pulled the drive belts one at a time but not able to pin it down. Replaced the power steering pump (it got worse, went back to original pump). Next is checking harmonic balancer. Thinking perhaps it is wearing at 217k miles and the slight increased load at low RPM is causing it to vibrate.

How do you check if a harmonic balancer is good other than by visual inspection? Mine seems to spin true, no obvious play in the rubber separator when I try to turn it by hand, not oiled up by a crankshaft seal leak, crankshaft bolt is tight.

 

You would have to look at the balancer.
The the inner hub and the outer belt drive part should be flat. If the two pieces have shifted, the belt drive hub will be out of alignment.