Just a check point. The relay is a 'normally open' relay. The power feed comes in on pin 30, when the relay is 'on' it supplies power to two pin 87's one pin feeds the fuel pump, the other feeds the lambda sensor heaters. If an incorrect (changeover) relay is used, or if the correct relay is faulty. it may power the pump, but fail to power the lambda sensor heaters. The result will be limp home mode, bad idle, and it will feel a bit 'tom and dick'
.
