98 S-10 2.2 90,000 miles surges and hesitates

my S10 is hesitating when i shift gears,after i get up to speed i can feel it surge a little bit. The service soon light is also on,i have put the following new parts on egr valve ,tps switch,02 sensor,plugs and wires. The dealer i took it to wanted 1000 dollars to install these parts i did it myself for about 350,the service soon light went out after installing these parts.But after driving 50 miles it came back on and started hesitating and surging again .The dealer said #3 fuel injector is going bad according to the computer read out that it is not firing right all the time and they want $350 per injector to replace , i can go to my local auto parts store and get an injector for $80 and do it my self .Iam running short of money and patience i would like to fix it properly instead of replacing all this parts and still have this problem!! If anybody has any suggestion i would really appriciate it.

mabe you go bad plugs or wires

plugs are brand new bosch platinums ,wires are brand new ac delco

mine is doing the same thing, they found no compression on the #1 CYLINDER, i'VE GOT 270,000 ON MINE

compression ok ,probaly will change fuel injector in #3 cyl and see what happens then ,just was wondering if any body else has had this problem and change out just one injector and it solves the problem.Then again Iam going on the word of the dealer ,its what they said the computer showed during a scan to see the why service light stays on