Toyota is reportedly searching for thousands of airbag parts being sold by dodgy importers that could cause airbags to malfunction in a crash.

A leaked email obtained by News.com.au revealed the company does not know how many counterfeit spiral cables were installed unknowingly.

The defective parts will only effect cars which have previously been in a crash, as the spiral cables are replaced after an airbag has been deployed.

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The Corolla is Toyota’s best selling car, and Australia’s most popular small car. Photo: Getty

After discovering the parts had infiltrated the local market, Toyota had them safety tested in Japan, confirming that they are potentially dangerous in a crash.

As a result, the car giant sent an urgent bulletin to its dealers, detailing the differences between genuine and non-genuine Toyota spiral cables.

Toyota “has serious concern about the safety of these parts”, said the bulletin.

Specifically, it said there were four ways the parts could fail in a crash, resulting in air bags not being deployed.

Toyota said this is due to a “high likelihood of insufficient conductivity to support airbag deployment electrical current”.

According to the bulletin, prospective buyers can tell when they are being sold a fake part, as it won’t have gold plated connectors, the crimping of the cable is not strong enough and it does not use copper wire as per the genuine article. The plastic locking tabs are also “poorly formed” or misaligned.

Unfortunately, Toyota-owners may be swayed by the price difference between the $300 genuine part and $50 counterfeit part.

Toyota, Australia’s best-selling car company for over a decade, has no idea how many cars could be affected by the third-rate parts.

But according to industry figures, about 150,000 require spiral cables to be replaced each year in Australia.

There has been speculation that the problem may not be exclusive to Toyotas, as the spiral cables are a commonly-used part for many brands.

This isn’t the first airbag bungle this year for Toyota, which was forced to recall side airbag inflators for both the Rav 4 and Echo in May.

The defective parts were recalled due to a risk the airbag could rupture and create metallic fragments to fly through the air.