Alfa Romeo 2.0 JTDM
The 2.0-litre JTDM with 163–170 hp replaces the old 1.9 JTD as the new volume diesel. Less displacement than the five-cylinder, but lighter and more frugal. Multijet II injection for improved emissions and smoother running. In the 159, Brera and Spider the most sensible diesel choice — enough power for daily use, lower running costs than the five-cylinder.
Strong-Pulling Diesel Estate
170 hp diesel in the Sportwagon: strong pull, economical, with the familiar 159 handling. For estate drivers who won't compromise on Alfa quality.
Engine Weaknesses 6
Like all JTDM engines on the 939 platform, the 2.0 JTDM tends to have the intake manifold coked by the EGR system. Swirl flaps can break.
Symptoms: Power loss, black smoke, limp mode, swirl flap risk
The VTG turbocharger on the 2.0 JTDM clogs with soot deposits. Vane ring jamming leads to power loss.
Symptoms: Power loss, unstable boost pressure, engine warning light
Identical to 939B1: the O-ring gasket between oil pump and oil sump flange of the 2.0 JTDm 170 hp (939B3) hardens and loses its seal. Brief oil pressure warning after cold start. Aluminium O-ring as permanent fix. Replace at the same time as the timing belt.
Symptoms: Brief oil pressure warning after cold start (~3 sec), then normal oil pressure
The dual-mass flywheel (DMF) of the 2.0 JTDm 939B3 (170 hp) wears like all JTDm derivatives. Higher torque and short-trip driving accelerate wear. Total dealer cost approximately 2,700 €.
Symptoms: Vibrations when pulling away, judder during rev changes, noises at idle
The swirl flaps of the 2.0 JTDm 939B3 share the well-known JTDm weakness. EGR soot deposits on flaps and linkage bush wear are the most common triggers. Blanking kit recommended.
Symptoms: Engine warning light P2279, power loss, stumbling, smoke
The EGR cooler on the 2.0 JTDM develops cracks in the core, allowing coolant into the EGR path and causing white smoke. A common temporary fix is deactivating the EGR cooler, but this violates emissions regulations.
Symptoms: White smoke from the exhaust, coolant level dropping with no visible external leak, engine warning light with EGR fault
Vehicle Weaknesses 8
The front subframe (engine cradle), rear axle carrier and sills rust without adequate factory protection. Particularly on TI models, areas behind trim panels corrode unnoticed. Subframe replacement costs approximately 1,000 € plus fitment.
The M32 gearbox (fitted to 1.9 JTDM and 1.9 JTS) develops bearing noise from around 100,000–190,000 km. Gearbox overhaul without removal costs approximately 1,100 €. Conversion to the more robust F40 gearbox is possible.
On the 159 and Brera 939, multiple electronic components can fail simultaneously: windows, air conditioning, Bose audio, xenon, door control units. A faulty body computer is the frequent cause. Replacement 800–2,000 €.
Control arm bushes and joints on the 159 front axle wear noticeably. A visual inspection at the time of purchase is recommended. At the end of their service life, pronounced knocking is clearly audible. Plan for renewal every 100,000–150,000 km.
The steering rack on 159 models up to 2007 tends to leak with squeaking and clicking noises when turning. A revised steering rack was fitted from the 2008 model year. A leaking rack puts stress on the hydraulic power steering.
The 159 cooling system (especially the 2.4 JTD) tends to develop air pockets, especially after repairs. Several bleed points must be observed. Symptoms: coolant boils over, heating only works at higher revs.
The 159's air conditioning regularly loses refrigerant through stone chip damage to the condenser or leaking connections. Correct fill quantity is 550 g — frequently only 490 g is added. Leaks are only visible via UV tracer after several days.
The brake discs on the 159 (especially the Spider variant) rust heavily after just 4 days of standing. Grinding and juddering occur when pulling away. After approximately 10 km the braking feel normalises, but disc wear remains elevated.
Reports & Tests
Only around 58.5 percent of seven-year-old Alfa 159s pass their MOT at the first attempt — a noticeably worse result than comparable German rivals. Diesel engines in particular cause significant problems up to and including total engine failure. Brake discs and suspension wear above average.