The car does not run smooth

Lets start at the beginning. Is the check engine light on ?
You have an idle air control valve which could be sticking open or shorted to ground. You should be able to unplug it to test. There also could be a gasket or hose that is opening up and causing a huge vac leak.

Try Maf sensor,(Mass air flow)
Then try tps sensor, (throttle position sensor)
Unable to answer exactly without looking up codes

on a cold start car will idle fast till it warms up then will drop to about 1000 rpm, try increacing idle speed so when it warms and drops it should stay idleing

I had a something similar to this happen to a girlfriend of mine. She has a 98 escort and it ran out of gas and the service engine soon light came on after she filled it up. If this is what your talking about check your owners manual. Most of the time if there is really nothing wrong with car you can drive it around ( Generally 20 min in town and 10 on the hwy with 4 idle periods (4 times of the engine being at idle) - do not cut engine off) and the light will go off. The rough idle code most likely happened when the engine ran roughly because. it was running out of gas.

Fuel pump may not supply enough pressure to run engine, but it could be a pluged fuel filter as well. you should get the code pulled out of the computer this will tell you exactly what is wrong or at least narrow down what is causing the problem. It could also be either bad gas with water in it or bad timing or wrong firing order.

try cleaning the throttlebody if that doesn't help unplug the mass air flow sensor and see if it smooths out

get a trouble code from Autozone or other store for free. It sounds like a sensor problem to me. The Idle Position sensor for example.

1. There is NO SCREEN.
2. Did the 'Check Engine' Light come ON? Whenever the 'CHECK ENGINE' light comes on, the ECU (Engine Control Unit) sets a Diagnostic Trouble Code (DTC). These codes identify the particular engine management system which caused the light to come on.
You'll need to use/find an OBDII (On-Board Diagnostic) Scanner to retrieve any code which have been stored in the ECU computer. Afterward, we might be able to help you DIAGNOSE the problem and perhaps eventually fix the problem.

You will need to check the fuel pressure, if it is on the minimum pressure side or lower then you will need to change the fuel pump.

Im not sure if you got it fixed yet! It could possibly be idle air control valve. But here some more suggestions! I had a 94 Safari van 4.3 liter I was working on for about three days and I finally figured out what was wrong with it. It would run fine for a couple minutes and as soon as I hit the gas and let off it would surge, but anyways I ended up changing the distributer, after the fuel pump and filter, mass air flow sensor, egr valve, idle air control valve, map sensor, and ignition module. So that might sove the problem if you were on the same track with it as I was. Hope this helps ya!