For the last few days the old motor has been hunting and idleing quite low. Basically found that the clutch for the aircon would not disengauge so i unplugged it. Eversince unplugging it it does not pop and bang on over run but shoots massive flames when it hits the rev limiter! Never did that before. Question is i can remember from my first rx an air pump that pumps air onto the cat does it work from the aircon pump?
Old car engine shown.
That is your air pump. The air-con compressor is on the other side of the engine, undernearth the power steering pump.