Hi guys i need help.
Last night i deristricted my air box on astra 1.8 coupe.
then wen i started it up it was lumpy idling raiseing and droping amd burble heard in exshaust....

Then i refitted the parts i took out and it still the same, there is no engine warning light showing so im puzzled. I then checked the sensor on the back of the aior box and it seems fine and it hadnt come uncliped. Also checked surrounding sensors.

Could the culprit be....

A.Throttle body needs a cleen with carb cleaner.
B.Mass airflow sensor.
Or C. The fact im running low on fuel, could it be a fuel pick up problem in the tank causing it to rase and dip.

Any assistance on the matter would be great thanks....