Hello everyone.This is my 1st post on this site. Excuse me 4 bad english and wrong spellings. I have a problem with my 89 190E 2.6. I posted the problem on benz world, got some responses, tried those but didnt help, so i may get my answer on this forum. Anyways heres the problem, there is a shake in the engine when the car idles, Seems like a missfire and the oil pressure and the economy guage keeps goin up & down a little bit, also i can smell fuel from inside the car. On starting the car, it seems that the engine is struggling 2 bring the idle 2 normal. Stays like this for 2 to 3 seconds then comes to normal, but then starts shaking. It only happens when the engine is warm, when its cold with rpm's high, it runs ok or when i start driving it, engine performs perfectly ok. got it checked by a mercedes expert, he said the fuel distributor is running rich on 1 cylender, so he was gonna do the tunup and adjust the mixture, he asked $500 4 the job without any guarentee's, so i didn't go 4 it. But ended up paying him $120. Later i changed the plugs, wires, rotor, cap myself, but problem remained. Today i took it to another shop, he adjusted the mixture,which was lean according 2 him, its performing alot better now, shakes are alot less, but still there, i paid $155 this time. Gas smell is still there but very little now.He says its an old car, so little bit of rough idle is normal. But i think, problem is a problem. Someone on the benz world suggested that it could b the oxygen sensor. Now it seems iam running out of options with the work shops, seems no body can detect the actual problem, and iam sick of waisting money without getting it fixed. Any suggestios will b highly appreciated. Thanx in advance.