I have a 1990 Olds 88. Recently it has started running rough / cutting out after the engine heats up. It seems to run fine at steady speed, most of the time. After it is warm, if you hit the gas it sputters really hard, no power at all. It doesn't matter whether you barely push on the gas or floor it, it cuts out. I have upgraded the ignition from the Magnavox to the Delco (94 Bonneville).
Things checked / replaced:
New plugs, plug wires and ignition system when I went to Delco ignition 6 months ago.
Checked plugs, all looked good.
Swapped ICM and Ignition coils with known working ones.
Checked fuel pressure: 42 key on/engine off, drops to about 35 at idle
Checked voltage/ohms on all injectors. Listened with stethoscope had ticking on all injectors.
Took catalytic convertor off
Replaced (ECM) computer
Replaced cam position sensor
Replaced Knock Sensor
Replaced PCV valve
Took EGR off and cleaned, plugged off to test and no difference.
Took IAC off and cleaned
I'm sure that I have left something else off that I have done. Nothing makes a difference. I am going to try the temperature sensor next. Any ideas or help would be greatly appreciated.
Thanks

 

Check your O2 sensors and Mass air flow sensor.