CarValidator

1.7 CDTi (Z17DTH / A17DTJ, Isuzu)

20042010 · diesel · 1686cc · 110hp

Engine codes: Z17DTH, A17DTJ, Z17DTR

Maint. Sensitive

Reliability, common problems and owner reviews for the Opel Astra H 1.7 CDTi (Z17DTH / A17DTJ, Isuzu). Check this before you buy used.

The Isuzu-derived 1.7 diesel — a tough, long-serving design widely regarded as the more robust diesel choice here. The main wear point is the turbocharger (loss of power, black smoke, whistle, often from ~100,000 km); EGR/DPF on later cars. Solid with maintenance.

Same engine, other cars

This is the same physical engine (A17DTS) sold under different names across brands. Reliability is broadly shared — cross-check these:

Known Issues

Turbocharger wearrecurring

Turbo wears from ~100,000 km — power loss, black smoke, whistle.

Fix / Workaround: Rebuild/replace turbo; check oil feed.

Repair cost: €400–€1000

Typically appears after: 100,000 km

EGR / DPF (later cars)recurring

EGR clogs; DPF blocks on short trips.

Fix / Workaround: Clean EGR; motorway runs for DPF.

Repair cost: €150–€700

Mileage Thresholds

After 100,000 km: Turbo wear window.

Pre-Purchase Checklist

  • Check turbo on test drive (smoke/whistle/power)
  • EGR/DPF history
  • The more robust diesel vs the 1.9 CDTi

Frequently asked questions

Is the Opel Astra H 1.7 CDTi (Z17DTH / A17DTJ, Isuzu) reliable?

Maint. Sensitive — The Isuzu-derived 1.7 diesel — a tough, long-serving design widely regarded as the more robust diesel choice here. The main wear point is the turbocharger (loss of power, black smoke, whistle, often from ~100,000 km); EGR/DPF on later cars. Solid with maintenance.

What are the common problems and reviews for the Opel Astra H 1.7 CDTi (Z17DTH / A17DTJ, Isuzu)?

The most commonly reported problems: Turbocharger wear, EGR / DPF (later cars).

Is a used Opel Astra H 1.7 CDTi (Z17DTH / A17DTJ, Isuzu) worth buying?

Fine if serviced correctly — but it punishes neglect hard. History and the right consumables matter.