Online searches for diesel vehicles on Auto Trader declined to just 42% in February following a “precipitous” decline in popularity for the fuel type over the past two years.

Auto Trader’s latest Retail Price Index report revealed that petrol now accounts for 50% of all fuel-related searches that take place on its marketplace, whilst diesel has slumped from 63% to 42% in since February 2017.

Two years ago searches by fuel type were made up of just 33% in petrol vehicle-related enquiries, Auto Trader said.

Karolina Edwards-Smajda, Auto Trader’s commercial product director, said that the ongoing decline in diesel searches “clearly highlights the impact a combination of sustained ‘demonisation’ and new legislation is having on consumer perception”.

Auto Trader said that the decline in enquiries for disel vehaicles has been most keenly felt in London, where an Ultra Low Emission Zone (ULEZ) comes into effect on April 8.

Searches for diesel vehciels in the capital have fallen by 37% in two years, it said, from 63% in February 2017, to just 26% last month.

In contrast, fuel related searches for petrol in London have spiked from 32% to 61% during the same period.

Low emission alternatively fuelled vehicles (AFVs), which will be completely exempt from the new ULEZ charges, have seen a growth in searches from 4% to 12%; significantly higher than the current total market (7%).

“Whilst the adoption of alternatively fuelled vehicles has been relatively slow, they are becoming more financially accessible and more technologically advanced with dramatically improved range capabilities,” said Edwards-Smajda.

“With our latest Market Report revealing that 71% of car buyers are now considering an electric vehicle as their next car, the trends we’re seeing today are only set to accelerate.”

According to the Auto Trader Retail Price Index, which combines and analyses data from over 500,000 trade used car listings every day, as well as additional dealer forecourt and website data, the values of used diesel vehicles is prevailing despite the decline in interest.

The average price of a second-hand diesel in the UK in February was £14,309 – a 2.4% increase year-on-year (YoY).

The performance represents a slower rate of growth for its petrol and low emission counterparts, however.

The average price of a used petrol last month was £11,249, marking a 2.8% increase on February 2018.

In terms of the whole market, the average price of a used car in February was £12,885, which on a like-for-like basis equates to a 2.7% increase on the same period last year.