Hey all,
I recently bought 03 g35 (02/02/2019). Ive already had to do am engine swap cause a simple catch can was hiding the fact it had a cracked head gasket. So I bought a engine a d installed it this last weekend. Now I'm hearing what sounds like some kind of metal dragging across teeth as I put my foot on the gas. It's also causing a vibration that can stopped by pushing down on the shifter ****. Please help cause I really like this car but I'm really starting to regret getting it cause I've already put so money into fixing it. Thank you in advance

 

I would start by doing a good visual inspection under the vehicle, if you can drive it down to a lube center with a pit you can get under it with a mechanics stethoscope and figure out EXACTLY where the noise is coming from.

Typically you can call ahead to see if they're busy and offer a $20 tip to stand under the car for a couple minutes to find the source of the noise, hell of a lot cheaper than paying a mechanics diagnostic fee.

Did you get all the bolts back into the bellhousing in the correct order and torqued properly? iirc there are 3 different sizes of bolts.