The 324td was released in 1987 to coincide with the facelift of the E30 range. The powerplant had already seen service beneath the bonnet of the E28 from 1985, and BMW decided it was now time to try a turbo in their smallest car. This would be the first turbo-charged small sedan since 1974, when BMW stopped the production of the 2002 Turbo.
The 324td was offered only in LHD, and came in a choice of two body styles; a 4-door Saloon or in the newly-released Touring. The trim level was basic, with specification tailored to economy rather than performance. although M-Technic Suspension was fitted to the car to cope with the increased weight.
Despite these features, the 324td is not considered a success in BMW history, and has the lowest production figures of any factory E30. Production ended with the last of the Tourings in 1994, with approx. 27,000 units made.
The 324td was never officially offered in the UK. However, some cars were privately imported and converted to RHD.
The M21 engine was a trusted engine by the time of the 324td's release, and had been fitted to a number of vehicles already. However, the application of forced induction technology is unique; this is the only turbo-charged model in the E30 range. While its engine was substantially different from the petrol versions, almost every other component was shared with the rest of the E30 family, including Suspension and Brakes.
The turbo itself was a variant of the standard T3 design, made by a company called AiResearch. The design included an internal wastegate, and complex emissions controls such as an EGR system were also fitted. These efforts pushed the power up to 115hp compared to the 324d's paltry 86hp, and made the 324td a popular choice among economy-minded drivers in continental Europe.
Other changes to the M21 engine included a more modern injection pump. However, the fundamental internals, including the forged steel crank shaft, cemented the diesel engine's reputation for reliability, even if performance was not equal to the 318i.
Because of its relatively low production figures, few 324td cars remain, and with the desirability of the internal components for turbo swaps and stroker conversions, those in bad condition are swiftly cannibalised rather than restored.