225 Check Injection, Check asr/esp, engine management light, limp mode

This really is a last ditch attempt to fix this.

Seems to be random, maybe affected by going up a hill but has just happened at idle in traffic. Turning off and on temporarily fixes it. Symptoms are "CHECK INJECTION" will appear sometimes followed by the service light and then spanner, "CHECK ASR/ESP" will start flashing and sometimes the engine management light will flash which puts it into limp.

I have changed the following since this started:

Coils
Injectors
Knock sensor
Throttle body gasket
Ripped wiring loom to bits and repaired damaged wires

Only fault I ever get is P0300 which is multiple misfire. Car has just been scanned with CLIP and gave the following (first two are probably me unplugging MAP sensors)

DF089 INLET MANIFOLD PRESSURE CIRCUIT
DF004 TURBOCHARGING PRESSURE SENSOR CIRCUIT
DF073 CYL 2 IGNITION CIRCUIT
DF074 CYL 2 IGNITION CIRCUIT
DF086 WATER PUMP RELAY CONTROL CIRCUIT
DF065 MISFIRE

These codes were cleared before wiring loom gate and wouldn't come back. Now it's fucked up again and without CLIP I'm getting P0300 again. Will get it plugged in again soon.

I am gutted TBH. If I can't fix it it's off to webuyanycar as I can't be without a car and this ones absolute shite.