Please help me identify these problems

Hey everyone, first of all before beginning I have a request for the Modertaors plz correct the Fiat sub-forum name to "Siena" .. thanks

I have a Fiat Siena there are alot of exterior designs in these past years, mine exactly looks like the top photograph from that page :
http://en.wikipedia.org/wiki/Fiat_Siena

Unfortunately I made a terrible accident back in 2010 you can check the story.details on my other post/thread (currently I have 2 threads) , the car condition is now not far from "terrible" because repairing shops and mechanics here in the country are stupid losers who don't understand anything they just copycat what their elder instructor/tutor once taught them back in their days when they were kids/teens (yes typically we have our mechanics learn their job that way, as a little kid who is taught/instructed by an older version of him and the cycle continues, and the legacy generally comes maybe from the foreign occupation, the egyptians then learned alot from the foreign people who were living here back in time) so they are a miserable failures they just know some basics and even I know a guy who don't know what's a Horsepower .. as I said before they are big losers/jerks

So for the most important part I gave up I don't want to fix any more thing, I paid alot of money and the car is still terrible after the accident ...

Some of the major problems that are noticed with time:
-The Car swallows/uses alot of Fuel/Gas
-Gas smell from muffler tip with a little white smoke
-An annyoing sound when I turn the steering wheel right and left
-The steering wheel is so heavy when the car is stationary
-Small amounts of fluid leak under the front of the car
-Front lights (left one) is not working or weak compared to the other one
*I repaired the broken headlights maybe the one who put in the new ones is the reason
-A strange/unidentified odor when I park the car after returning from university (it seems as if it is heat or something)
-Car is slower than before accident and rpm is going so high
-Car suspension system is really screwed
*when I leave the steering wheel the car randomly moves(right or left) out of lane on the freeway
*Weird sounds from the suspension system when the road surface is not great
-The front left passenger's electric window is opened so slow compared to the driver one.
-When I start the car in the morning while still stationary/before moving, the rpm suddenly drops as if the car is turned off for some seconds then it returns back to 1000 rpm (sometimes it's at 2000 rpm while station too)
-Car engine sound is not great as before (they say that the block was broken/cracked so they weld it as a fix can this be the reason)

Finally, how can I identify my engine, and know whether they replaced it with another from the junk old engines

thanks in advance

It seems all the car parts have been screwed up badly.My suggestion would be rebuild it again at a good workshop if you can find all the spares otherwise dump it.

It seems all the car parts have been screwed up badly.My suggestion would be rebuild it again at a good workshop if you can find all the spares otherwise dump it.

Dear SierraB I have an idea and I want your comment, my idea is that I can build it again but with better parts I mean something like an upgrade or modification or even tuning, would you please suggest me the complete tuning parts if you know well in this field (for example new braking system, new suspwnsion system etc... but don;t forget it's a FIAT so I need the parts to be related )

and do you know a place that exports Car engines even if used but in good condition ? I really need a FIAT Barchetta engine it will be great but can it fit inside my car ??