At least one-in-10 dealers are still unaware of the Worldwide Harmonised Light Vehicle Test Procedure (WLTP), despite a September 1 implementation deadline for the fuel economy test regime.

The revelation comes from Manheim’s latest dealer sentiment survey, which showed that 14% of dealers admitted to not knowing what WLTP is.

Last month, Manheim revealed that a third of car dealers were unaware of the date that the new WLTP fuel emissions test comes into force.

The vast majority (91%) of the dealer sample said that WLTP has contributed to a lower September order take compared to last year.

With stock availability concerns increasing as WLTP looms on the horizon, just over half of those dealers taking part in the survey said they have pre-registered stock in August to overcome WLTP related issues.

Philip Nothard, head of external relations at Manheim's parent company, Cox Automotive, said: “As we get ever closer to WLTP being implemented, having one in ten dealers admitting to not knowing what WLTP is, frankly is quite shocking.

“When this new revelation is added to our previous dealer sentiment survey finding that a third of dealers were not aware of when WLTP comes into force, it demonstrates in quite stark terms the amount of confusion and ambiguity that still exists around WLTP.

“These dealer concerns along with the lack of awareness and uncertainty that still exists should be deeply concerning to the industry as WLTP gets closer to being implemented.”

All new vehicles homologated since September last year will have undergone the new testing procedure, designed to provide more realistic fuel economy and emissions figures that the outgoing New European Driving Cycle (NEDC).

From September 1 2018, all existing models on sale must have been re-tested.

The switch has led to confusion throughout the automotive industry, as cars tested under WLTP –then re-calculated back to an NEDC equivalent - are returning figures that are on average 10g/km higher than under the old test.

Commenting on the apparent confusion that still exists among car retailers, National Franchised Dealers Association (NFDA) duirector, Sue Robinson, said: “It is concerning and disappointing to see that one-in-10 dealers is still unaware of the introduction of the WLTP testing in September for all new cars.

"NFDA has repeatedly contacted individual manufacturers to urge them to provide their respective dealer networks with clear guidance on the matter and to encourage dialogue between them.

"In July, we also held a workshop to help dealers address the potential implications of WLTP. Going forward, we will continue to offer assistance and guidance on the issue to our members who may need any clarification."