1996 Oldsmobile (EightyEight)Car shakes a wobbles when stopp

P0401=EGR insufficient flow, remove the EGR and clear out the port it's blocked with carbon, I use a piece of steel coathanger, the backfire, may have ruined the idle air clontrol valve, it's bolted to the throttlebody with 2 screws...replace that.

Thank you for quick response. Please note it was not shaking and wobbling when I got the code couple weeks back. It started yesterday. Is this still the problem witm with EGR?
Would you please let me know, How much would it cost if I take it to mechanic? Just to get an idea for this fix... Appreciate your help

I checked new codes and those are PO108,PO171,PO300
My mechan is on vacation so checked with other mechanic. He told me I have to change fuel hose and gaskets, Is this diagnostic correct? What should be done to fix this. Please elt me know... appreciate your help on this...

P0108= MAP/Baro circuit high input
P0171= System too lean bank 1
P0300=Random, multiple cylinder misfire detected.
All can be caused by fuel deliver problems, I don't see an EGR related code here? Can also be due to vacuum leaks!
You may have a vacuum leak, get a can of spray gumout, spray the vac lines and maniflod area, when the idle changes, youve found the leak! You want the engine running and spray on the outside but do direct the stream onto the hoses, if it is a vacuum leak, the engine idle will change speed, then you have detected a leak, repair the vacuum leak and see how it runs! If that doesnt do it, you may need a new idle air control valve, it's bolted to the throttlebody

Thank you for your response... would it be due to damaged spark plug wires? As I had heard a small explosive noise before it started shaking and wobbling... Your opinion is appreciated... What is gumout spray??? I will also try checking the leak and will let you know the results...

Misfires, which you heard as the explosion, can be bad tune up parts, including plugs, wires, and coils.