91 honda civic dx 1.5L quit running properly. Starts, runs for a few seconds just fine then stumbles and starts running rough, check engine light comes on then it stalls. Started as an intermittent problem. I have ruled out the fuel pump. I changed the fuel filter, spark plugs, distributor cap, rotor cap. I checked the ignition control module and ruled out the catalytic converter. Has spark at all four plugs and is getting fuel. I can keep it running by revving the engine but it runs really rough. When I shut it down and restart it runs fine for a few seconds then starts running rough again. Nothing I have done to it so far has changed its symptoms.