Get someone to listen to make sure the fuel pump is actually running when the engine is.

Check connections to all the sensors at the rear of the manifold - take your time and pin them out with a meter to the ecu plug, the wiring diagram is in the Haynes manual.

When it is running, and it is struggling, very gently depress the metering flap to richen the mixture. If it is better, then it is lean, if worse, it is rich.

Rick