Alfa Romeo Repair: HICCUPS, coolant temp, lean condition

Question
My 91 164 has developed a bad case of the hiccups......While driving, the engine intermmitently cuts out for a fraction of a second. When this happens, the tachometer drops to 0, the check engine light comes on and the car jerks back and forth agressively.  It's intermmitent, but happens continously. It idles fine and the problems persists at any speed.  I have replaced the fuel filter, dist. cap/rotor, coolant temp. sensor and air filter.  The intake air hose looks OK.  I'm planning on replacing the plugs and the wires next because I just purchased the car and I don't know how old they are.  I checked for ECU fault codes and I originally got a 1-2-2-3 code which led me to believe that I have a bad O2 sensor.  I went ahead and cleared the ECU's memory and the code has not resurfaced.  Any suggestions/ideas? Thanks!

Answer
Replace the sparkplugs with NGK BPR-6ES unless you keep it above 3K RPM and then use NGK BPR-73S. Replace the O2 sensor--it is faulty and creating a too lean condition. If this does not clear it up give me more information. Did you change the oil. Use 10w-40 or 5w-50