Whinning noise from engine/restricted acceleration
 

2006 dodge charger v6 3.5... whinning in engine. More so upon acceleration. The other day while driving it slowed and wouldn't accelerate. I cut it off waited a few minutes, started it up and tried to accelerate. It moved approx 200 ft then stopped accelerating. I've only had the car for a year, so I don't know the age of the transmission. I also have a constant misfire reading on 5. I've changed the spark plugs so far. I reset it. I forgot to mention the code of the engine being to cold. In which I took to a mechanic. He changed thermostat twice, then the sensor behind it. Codes are still there. Please help.

What are the exact codes?

I was told to reset it, now I have none and can't really drive it around.

It was suggested by a NAPA employee that I reset it and if I was having the same symptoms then it was either the pcm or ecm. I tried driving around the yard to get the codes to pop on but they haven't. However, it will drive forward with no problems until I put it in reverse. After placing it in reverse, I have to cut the car off, let it sit for a while and retry. When placing in any gears I hear a thump every time I shift from park to drive or others.

Best bet is to take it to a dealer or shop for proper diagnosis.