2.4 JTD / JTDm Multijet engine: faults and reliability

• 2.4 JTD 10V (136-150 hp, 1998-2007)

  1998–2007 · 136–150 hp

  Buy

  Auto Świat says the 10V breaks down relatively rarely on its own and that its faults tend to come from lack of maintenance and wear (small oil leaks, air-flow meter, crankshaft sensor and high-pressure pump), with a fairly durable injection system. The 156 page has testimonies of 136 and 150 hp cars with between 219,000 and 394,000 km. These are cars more than 18 years old: demand the invoice for the last belt and water pump change.^[1][4][7]

• 2.4 JTDm / Multijet 20V (175-185 hp, 2003-2009)

  2003–2009 · 175–185 hp

  With caution

  Auto Świat describes the 20V as more complex and more failure-prone than the 10V. On the 175 hp 156 page (29 testimonies) the most-cited items are the EGR valve (7), probes and sensors (6) and the turbo (3). We have not found testimony pages for the 166 or the Thesis. Worth buying with the invoice for the belt and water pump and by checking the EGR and the particulate filter (if fitted).^[1][7]

• 2.4 JTDm / Multijet 20V 200 hp (2005-2011)

  2005–2011 · 200 hp · 939 A3.000

  With caution

  This is the version with the most documented weak points: the intake manifold flaps (Fiat acted in 2007) and the EGR valve (24 mentions in 63 testimonies for the 159). The 159 testimonies also cite the particulate filter (18) and the cylinder head (4 for head gasket and 5 for cylinder head), although we have found no press to confirm it. Buy with the 2007 action carried out, the EGR and DPF history in view and the invoice for the belt and water pump.^[1][2]

• 2.4 JTDm 20V 210 hp (Alfa Romeo, 2007-2010)

  2007–2010 · 210 hp · 939 A9.000

  With caution

  Auto Świat says this version does not suffer from the manifold flap failure, although Diariomotor (2024) calls it "very reliable" but attributes to it the same "butterfly flaps" problem as the 16-valve diesels. The voluntary 159 testimonies record 13 mentions of DPF, 8 of EGR and 5 of turbo in 36 testimonies, plus one case of five faulty injectors at 93,000 km. Worth buying by checking the DPF, EGR and turbo.^[1][2][8][9]

Buy: No known serious faults, or they have already been corrected, in this version. With caution: Worth buying if something specific is verified: history, a replaced part or a completed campaign. Avoid: High risk of a serious fault that is hard to check for or prevent.

1. 1Medium severityFrequency: OccasionalIntakeIntake manifold flap failure (swirl flaps)According to Auto Świat, the intake manifold flaps of the 200 hp 2.4 JTDm often failed and left the car without power or in limp mode. In 2007 Fiat launched a corrective action that replaced the manifold, injectors and EGR; the 210 hp reportedly does not suffer from it, although Diariomotor disagrees.
2. 2Medium severityFrequency: OccasionalEmissions controlClogged or faulty EGR valve on the 2.4 JTD and JTDmThe EGR valve is the most-cited fault in the testimonies for the 200 hp 2.4 JTD of the Alfa 159: 24 mentions in 63, plus 8 in 36 for the 210 hp and 12 in 64 for the 156. It gets dirty or fails; RACE puts the cost of replacing an EGR between €130 and €800 on cars in general (not a price specific to this engine).Repair (garage): €130–€800
3. 3Medium severityFrequency: OccasionalInjectionInjector failure and diesel leaks on the 2.4 JTDmThere are injector failures on the 2.4 JTDm: 9 mentions in 163 testimonies for the Alfa 156 and 159. A 2008 210 hp lost five injectors one after another at 93,000 km, with diesel leaks, and Fiat's 2007 action on the 200 hp replaced all the injectors.
4. 4Medium severityFrequency: OccasionalClutchDual-mass flywheel and clutch wear on the 2.4 JTDThe flywheel of the 2.4 JTD appears in 11 mentions out of 163 testimonies (6 on the Alfa 159, 5 on the 156), often together with the clutch and between about 113,000 and 200,000 km. Auto Świat warns that on the 10V replacing the dual-mass flywheel can be expensive and that not all parts are easy to find.

Severity colours: low, medium, high, critical. How we rate them

Manufacturer

Fiat

Family

JTD / Multijet de cinco cilindros en línea

Fuel

Diesel

Displacement

2,387 cm³

Cylinders

5

Fuel system

Turbo

Injection

Common rail

Timing

Timing belt (dry)

Power

136–210 hp

Peak torque

400 Nm

Production

1998–2011

Makes

Alfa Romeo, Lancia and Fiat

Technical data^{[1][3][4][5][6]}

1. 1998–2007

   2.4 JTD 10V (136-150 hp, 1998-2007)

   First common-rail generation of the five-cylinder, derived from the pre-chamber 2.4 TD: it introduced a different injection system and cylinder head (still with two valves per cylinder) and a variable-geometry turbo. Auto Świat places it around 1998, less than a year after the 1.9 JTD of 1997, and gives 136 hp at Alfa Romeo and Lancia, then 140 and 150 hp with new injectors for Euro 3. Italian Wikipedia gives the 156 136 hp (1997-2000), 140 hp (2000-2002) and 150 hp (2002-2003). We have not found the engine code for this version.^[1][3][15]

2. 2003–2009

   2.4 JTDm / Multijet 20V (175-185 hp, 2003-2009)

   Second common-rail generation (Multijet at Fiat and Lancia, JTDm at Alfa Romeo) from 2003, with four valves per cylinder and more injections per cycle; the particulate filter was first optional and then standard. Italian Wikipedia gives the 156 175 hp from 2003 to 2006; the Lancia Thesis has 175 hp (2003-2006) and 185 hp from 2006, and the 166 has 175 to 185 hp depending on the model year. We have not found the engine code.^{[1][10][13][15]}

3. 2005–2011

   2.4 JTDm / Multijet 20V 200 hp (2005-2011)

   The 200 hp (400 N·m at 2,000 rpm) version of the 20V, available from 2005 according to Auto Świat, in the Alfa Romeo 159, the Brera, the Spider and the Fiat Croma II. German Wikipedia gives 159 production of the 200 hp as 09/2005 to 11/2010; a supplier's catalogue lists it up to 03/2011 for the Brera. The code 939 A3.000 appears in that catalogue for the 200 hp Brera; we have not seen it confirmed for the other cars.^[1][5][16]

4. 2007–2010

   2.4 JTDm 20V 210 hp (Alfa Romeo, 2007-2010)

   Version exclusive to Alfa Romeo (159, Brera and Spider): 210 hp and 400 N·m at 1,500 rpm. German Wikipedia gives its production in the 159 as 05/2007 to 11/2010 and French Wikipedia says the 210 hp Q4 version disappeared from the 159 range in the summer of 2010; a spare-parts catalogue lists it up to 11/2011. The code 939 A9.000 appears in that catalogue for the 210 hp 159.^{[1][5][6][17]}