Fuel Pump question?

Hello, I have a 92 buick regal that I cant seem to get to idle correctly. It has a roughness/shake to it and im getting grayish smoke out the exhaust when its revved up past 4000rpm at idle. but if I rev it up it shakes as it revs thru the rpm's.. but if you gently increase the rpm's it does it alot less. I have changed the computer,ignition module,fuel injectors,fuel filter, O2 sensor,intake manifold gaskets, replaced ALL vac lines, MAF sensor, Temp sensor,IAC valve, spark plugs and wires, given it fuel injector cleaner *sea foam*, TPS voltage checked, crank sensor, Ran a compression check and all come out even at 160.. I can only think fuel pump..but would a fuel pump give me these symptoms? I mean the engine runs,holds a steady idle and doesnt die but its shaking, rough idling and giving me smoke of a Rich condition.. but if the pump was bad wouldnt it be running lean..not rich?

Any advice would be appreciated

Thank youFuel Pump question?My guess is coil packs.

It sounds like its a mis-fire, not a fuel issue.

If you can rev it that high, you are getting enough fuel.

Check the coil pack.
Fuel Pump question?
have it pressure tested and replace fuel filter and look at pressure regulator
Fuel Pump question?
one of the ignition coils may be weak..
To me, it sounds like you have a timing issue. Like your distributor may have come loose and turned. Check your timing before spending money you don't have to.
Has to be one of the coils in the coil pack, you have replaced half the car and thats about the only thing left.
If its a stick(manual trans) you could have a broken spring in the fly wheel(duel masted fly wheel) or worn out flywheel.

Also check to see that all your fan blades are on your cooling fan. One plade missing will act just like a dead missing cylinder.

You could have a bad wire from coil to spark plug too. If they are coil over plugs(mounted on the spark plug) check the boots(wires) for any burns or holes.

Sounds like you have replaced everything else.