Alfa Romeo 1.8 MPI
The 1.8-litre MPI is the weakest engine in the 159 line-up — 140 hp from a naturally aspirated engine without turbo, without direct injection, without any technical highlight. Underpowered for the heavy 159 (1,450 kg): overtaking requires planning, gradients require patience. However, it is simple in construction, cheap to maintain and reliable.
Entry-Level Petrol Without Fire
140 hp 1.8 MPI in the heavy 159 — enough for the motorway, no more. Not a bad car, but the engine doesn't match Alfa's emotional promise.
Engine Weaknesses 6
The 1.8 MPI uses a timing belt drive. Replacement at the manufacturer's interval is mandatory, as belt failure causes engine damage.
Symptoms: No warning before belt failure, immediate engine damage possible
The 1.9 JTDm swirl flap system wears at the bush and actuator rod. Flaps can break, seize, or drop into the combustion chamber — catastrophic engine damage is possible. EGR coking worsens the problem.
Symptoms: Engine warning light, power loss especially at low revs, rough idle, smoking
The 1.9 JTDm EGR cooler leaks internally and allows coolant into the exhaust duct. White smoke and coolant loss mimic head gasket failure. Extensively documented in the Alfisti Forum for 159 / Spider / Brera.
Symptoms: White smoke briefly after cold start, coolant loss without oil-water emulsion, occasional exhaust smell inside the cabin
The 1.8 MPI tends towards elevated oil consumption from around 150,000 km due to hardened valve stem seals.
Symptoms: Blue smoke on cold start, elevated oil consumption
The pre-heating system fails through faulty glow plugs, corroded signal cables, or a failed relay. The message 'pre-heating system unavailable' appears even with intact plugs. Check the wiring harness at the control unit.
Symptoms: Difficult cold start, 'pre-heating system unavailable' message, extended pre-glow time, stumbling during warm-up
The thermostat can stick in the open or closed position. If it stays open, the engine fails to reach operating temperature; if it stays closed, the engine overheats. Replacing the thermostat eliminates the problem permanently.
Symptoms: Coolant temperature stays permanently low or does not reach 90 °C, heater blows only lukewarm air, elevated fuel consumption
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.