Drivers bought nearly 1.48 billion litres of petrol in July 2013 - an 8% fall on the June 2013 figure.
This was only 45 million litres more than the record low in February this year and just 11 million litres more than the January 2013 total.
July 2013 sales of diesel were down 5% on June's, dropping to just over 2.21 billion litres. These figures include commercial usage.
The AA said that in June 2013, when the average cost of petrol levelled at 134.6p a litre after surging to 140.0p in the spring, stable lower prices lifted petrol sales to a level last seen in November 2011.
But last month, a sudden 5p-a-litre rise in wholesale costs raised the average pump price from a low of 133.7p on the last day of June to 135.8p by the middle of July and 137.2p by the end of the month. It finally started to level off at 137.6p in the first week of August.
Tax income from duty on petrol and diesel sales fell £142 million in July compared to June and £35 million compared to July 2012, the AA said.
"Not only are petrol sales shadowing the record lows of this winter, but are lower than last July which included a week of Olympics football, opening ceremony and initial events."
He went on: "I t seems that, as each penny increase registers on fuel forecourt price boards, drivers automatically cut back - even if they're in the mood to spend elsewhere."