hi as above the engine is in a mk2 orion formally a 1.6 efi.
My engine is now driving brilliant, and pulls well in gear, etc, but when im cruising slowly in say 3rd gear (or any in fact) with low revs, such as when foot is just on the throttle and no more it becomes lumpy feeling, and when idling its a bit rough too. Engine backfires when on over run in gear and is burbly from exhaust at idle too, but when driving under load all is well. Anyone have any ides what this could be. I dont know what affect the tps sensor would have if faulty?