So I've got codes saying that I have misfires on cyclinder 1, 2, 4, and multiple/random. I've already replaced the plugs with new OEM NGK's the car came with, and I've replaced the coils with a new pack I purchased off ebay. After replacing each of those problems the car seemed to work fine again, and slowly started misfiring more frequently over the period of about a week or two. I can actually make the car misfire. If I am on the highway going steady at about 60-70 MPH and I let my foot off the accelerator for a second and let it wind down a bit, and then put my foot back on the accelerator to get it back up to speed it will start to stutter, and the engine light will flash. It also happens when I first start my car up and reverse down my driveway. It stutters a bit and almost feels like its going to die (no flashing engine light however). When I put it in gear and drive off slowly its okay again. It also seems to happen when taking turns. If I take a sharp turn you can feel the power give out and it doesn't accelerate like it should. If there are any suggestions as to what could be the problem with my fit I'm open for any help I can get at this point (I hate taking cars in to the shop).

 

It is hard to give advice without actually seen the car
The eBay sometimes sells cheap copies/ defective parts/ parts with expired shelf life.
How many miles on the car?
Have you tightened the new plugs correctly?
Lack of power cold may indicate valves out of adjustment (valve leak perhaps); in this case the car will have very high HC in emission.

 

160,000 miles on the car.

What do you mean by tightening the plugs correctly?

 

Renting small torque wrench from AutoZone and tighten plugs to specified torque on COLD engine.
I saw few times the plugs coming out with seal gasket not compressed.
I have heard about misfire monitor (similar to code scanner that counts misfires as they occur) not sure how much it costs and if its connector is Honda DLC3 compatible.
If you still have your old plugs, can you swap them back one by one and see if it changes anything.
On 07 V-6 Camry ONLY one cylinder had defective coil; it throw codes for random and 3 cylinders more. Thankfully there was another code indicating problem with coil circuit.

 

Most likely bad coil packs, China coils won't work for more than a month or so, if you're lucky. Spend some money on OEM ones (50 dollars a piece on Rockauto) and you'll be good to go.