Renault Laguna Turbo

Renault Laguna Turbo: from the 1.9 DTI to the dCi era, five 100% diesel engines

Unlike other models in the Renault range, the turbocharged Laguna has never included a petrol turbo version in this catalogue: every engine covered here is diesel. This distinction matters when it comes to the turbo — the earlier DTI generation uses fixed-geometry turbos with a wastegate (engine codes F8Q and F9Q on the first 1.9 versions), whereas the more recent dCi generations use variable-geometry turbos, notably the 2.2 dCi (codes G9T) and the 2.0 dCi (code M9R 740). Variable geometry subjects the vane adjustment mechanism to far greater thermal stress and carbon build-up than a simple wastegate: this is the first thing to establish before placing any order.

Identifying your engine precisely: engine codes and power variants

The 1.9 DTI covers the following codes: F8Q 784, F8Q 786, F9Q 710, F9Q 716, F9Q 717, F9Q 722, F9Q 730, F9Q 731, F9Q 734, F9Q 736. The 1.9 dCi spans a power range from 92 to 125 hp, with distinct codes depending on the exact version: D 4192 T3, F9Q 650, F9Q 664, F9Q 670, F9Q 674, F9Q 680, F9Q 750, F9Q 758, F9Q 759, F9Q 800, F9Q 803, F9Q 804, F9Q 808, F9Q 812, F9Q 816. Two 1.9 engines from different generations may share the same engine capacity but do not share the same turbo: the engine code stamped on the block is the only reliable reference. Confusing DTI with dCi, or mixing up the different power outputs within the 1.9 dCi range, is the most common ordering mistake on the Laguna.

Failure causes and points to check before fitting

On the variable-geometry turbos of the 2.2 dCi and 2.0 dCi, seized or stiff vanes are a common failure, often made worse by a clogged EGR valve or diesel particulate filter sending soot-laden gases back through the CHRA. On the 1.9 DTI wastegate turbos, bearing wear and oil seal leaks are the predominant issues, typically caused by degraded engine oil or overdue oil changes. In both cases, a whistling noise under acceleration, a loss of boost pressure, or the onset of limp mode are warning signs that should not be ignored. Regardless of which engine is involved, identifying and addressing the root cause of the original failure is essential before fitting a new turbo — otherwise the new part will be exposed to the same conditions that destroyed the previous one. All turbos listed on this page are new parts, sold direct.