Alfa Romeo 1.9 JTDM 16V
The 1.9-litre JTDM 16V with 150 hp — the better choice among the 159 diesels. 16 valves deliver more refined running and more power than the 8V. 320 Nm of torque propels the 159 with ease. Turbo and injectors are the main wear items at high mileage.
Diesel Estate for High-Mileage Drivers
150 hp diesel in the Sportwagon — economical and fit for daily use. The right choice for the family man, more of a compromise for the Alfista.
Engine Weaknesses 6
The 2.4 JTDm shows sporadic oil pressure loss at ~120,000 km. Cause: oil pump drive, blocked oil passages, or hardened gasket on the oil suction pipe. Documented in Alfisti Forum with a 2009 Alfa 159 2.4 JTDm at 120,000 km.
Symptoms: Sudden oil pressure warning 'oil pressure too low — stop engine', rough running after start, no pressure build-up at higher revs
EGR system cokes up the intake manifold. Swirl flap breakage can lead to engine damage.
Symptoms: Power loss, black smoke, possible swirl flap failure
VTG turbocharger clogs with soot. Vane ring jams, unstable boost pressure.
Symptoms: Power loss, unstable boost pressure, engine warning light
The dual-mass flywheel (DMF) of the 2.4 JTDm (939A2) wears like all 2.4 JTDm variants. Documented failure at 85,000 km; second failure at 157,000 km. Total dealer cost approximately 2,700 €.
Symptoms: Vibrations and shudder at idle and when pulling away, metallic noise during rev changes
The oil feed line to the turbocharger can develop leaks at fittings or crack at the metal flares. Oil starvation of the turbo quickly leads to bearing damage. Timely replacement of the line prevents total turbo failure.
Symptoms: Oil loss around the turbocharger area, blue smoke from the exhaust, turbo whistling, oil pressure drop under load
On the 1.9 JTDM 16V, the vacuum pump gasket also ages and leaks oil. In the worst case, vacuum pump failure can damage the camshaft, as the pump sits on the cam and is driven via a slot-and-drive connection.
Symptoms: Oil loss at the front of the engine, hard brake pedal feel, scraping or squealing from the camshaft area
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.