When placed in gear, sputters and usually stalls unless I pump gas pedal. Pumping lightly keeps engine running. With Heavy pressure, usually stays running, but barely fires, engine won't rev, and car won't accelerate. Pumping gas lightly but rapidly will get eventual acceleration. When engine gets good and warm, something seems to "click" (figuratively, not audibly) and engine takes off like no problem. Also, sometimes during sputter mode, flooring pedal will sometimes get "click" mentioned above.
ECM gives lean O2 sensor warning only. With ECM open, and measuring O2 sensor amp output, during smooth idle, voltage fluctuates between about
1.8 and 3 volts about once per second. Haven't monitored in rough idle. Checked fuel pressure with engine off and fuel pump relay bypassed at about 4.5 PSI steady. Fuel flow looks reasonable, though I didn't measure it precisely. Intake manifold vacuum is a steady 20 in. Hg during smooth idle.New plugs last year, though originals looked clean. All vacuume lines okay. Since trouble, have replaced (all original 134K): fuel filter, dist. cap / rotor, O2 sensor, H2O temp sensor, and EGR valve. Nothing has helped at all. Tired of pouring money. Need help. Somebody please?
Smokin Leroy