Starter tried to engage but it just keeps cranking?

So when I got the car I was told it had overheating problems. Replaced the radiator, thermostat, radiator fan sensor, and bypassed the heating core. The car would drive longer and longer since I have made those repairs. Then out the blue I got a throttle bottle indicator on my dash and a couple of weeks later the car wouldn't turn back over. Started making this horrible screeching noise like a belt getting sawed. Cleaned the throttle. Put a new starter in and fully charged my battery. Replaced the ignition relay and any fuse I didn't have or might have been damaged. I even replaced the spark plugs. Car still wont turn over. All of the lights and radio are still working but I really don't know what to do at this point. The one mechanic I took the car to said that my timing belt was bad. But after a lot of hours of reading articles and watching videos. I didn't think that was the problem. Please if anyone can help or tell me what I should do. I also replaced the battery terminals.

Dealership said my transmission pump was bad, so I replaced pump. Now car wont start. It ran fine before changing pump. Had the car jacked up pretty high on one side and battery disconnected for couple weeks. Any idea what the problem could be? Also, no codes are coming up.

Tried all reset security options you suggested, still not starting. I do not think it was bad, but replaced crank sensor located on nag 1 transmission bell. Still not starting.

Checked fuel pump, it's good. Not showing any codes, but battery was disconnected for awhile and it hasn't started since. Checked ground on transmission, that's good. There is just the one ground there, right? Another thing, should the engine have power going to it even when key is off? The fuel injectors and ignition coils still light up even though key is off. Also I put a new cam position sensor on it. I can't figure it out!

Car has been at dealership now 2 weeks and replaced PCM all fixed.

I swapped out a 2007 3.5 liter motor from my charger, and installed a 3.5 from a 2005 Chrysler 300. The swap went well. My only problem now is getting injectors to work. Fuel pump primes and runs while cranking. Pulled a cam sensor code then soon after crank sensor code. Tonight I replaced both sensors and finally got it want to start, but only starts with ether.I checked all ground straps wiring all looked good.I stayed with my original harness just switched out the sensors.I guess my next to do is invest in noid lights and or the adapter to check fuel pressure as I see no other way to check injectors pulse. Any input I can appreciate.

Thank you 2CarPros. Com for your speedy response in regards to my last post.I went ahead and replaced both cam and crank sensors (new ones).I'm getting fuel now, and spark. Only it wants to start it seems in only one spot. Almost acts as if it's 180 degrees out on timing. Distributor less is this possible?I figure I'm losing ref. Signal somewhere along the line, and then out of nowhere the # 15 fuse under hood starts to acting up intermittently blowing the fuse. Tracked that down to a little diode type looking part bolted on back of passenger side cylinder head. It has like one wire terminal and grounded?
So I decide to check compression while I had access, but then I couldn't find my gauge.I had no choice at time but go Old School and had my wife bring out Bounty paper towels.I admit and don't recommend this procedure to test compression but my choices were limited and the little lady with paper towels was not taking kindly to my after hours project so to speak.I can say compression was good enough to shoot out paper towel about eight feet or so high. If nothing else I would think it was enough to make it run?If timing belt was jumped it would affect compression?I'm not too eager to pull front cover on this thing, but I see no other way of checking the timing on this 3.5 Dodge. If any body has any input on this feel free to respond thank you.
P.S. I'm new to this post my first actually, And I have to say that taking time out to listen to our car problems and help out with out charging an arm or leg Is Priceless to Professional or Shade Tree Mechanics alike, we never stop learning and as we grow older we do forget some things. And this site is really a plus. As my wife reminds me everyday goes by that I should have just spent the $1,800.00 go figure.

Every other thing is good but just coil is sparking for the to start. I change the crankshaft sensor. If on ignition there is currant on coil but not spark to start?