Engine Mechanical problem
1985 Mazda GLC 4 cyl Front Wheel Drive Manual 290000 miles
my car was running fine up until a week ago. It will not idle at all when I start it I have to keep the gas pedal pushed in at all times to keep it from dieing. I have tried adjusting the idle speed screw but now all it does is idle from 800 to 2000RPM periodically, then just die out again. I just replaced the spark plugs wires and coil on it thinking it wasn't running on all cylinders but its still doing it. I checked all vacuum lines and they seem to be all in order. I even cleaned the throttle plates and the jets on the carburetor. Im all out of ideas and would be very thankful for any help.
on a side note it does surge when I push the accelerator to the floor and have the engine above 3500 rpm. Only when in gear it revs fine though