Nissan VQ23DE

The Nissan VQ23DE is a 2.3 l (2,349 cc, 143.34 cu.in.) natural aspirated V6 60° 4-stroke gasoline engine from Nissan VQ-family.

The VQ23DE features a lightweight aluminum block with a fully balanced four-bearings crankshaft and two aluminum heads with two camshafts (DOHC) and four valves per cylinder. The Nissan VQ23DE engine is equipped with CVTC system on intake valves and NDIS (Nissan Direct Ignition System) with individual coils on each spark plug.

Cylinder bore and piston stroke are 85.0 mm (3.346 in) and 69.0 mm (2.717 in), respectively. Compression ratio rating is 9.8:1.

The Nissan VQ23DE engine produces 173 PS (127 kW, 171 HP) at 6,000 rpm of maximum power and 225 Nm (22.9 kg⋅m, 166 lb⋅ft) at 4,000 rpm of torque. The NEO VQ23 produces 177 PS (130 kW, 175 HP).

The breakdown of the engine code is as follows:

• VQ – Engine Family
• 23 – 2.3 Liter Displacement
• D – DOHC (Dual Overhead Camshafts)
• E – Multi Point Fuel Injection

General information

Cylinder block

The VQ23DE has an aluminum cylinder block with a four-bearings crankshaft supported system, forged steel connecting rods, a micro-finished one-piece forged crankshaft. The crankshaft journal diameter is 60 mm (2.36 in), the crankpin diameter is 45 mm (1.78 in).

The cylinder bore is 85.0 mm (3.346 in), piston stroke is 69.0 mm (2.717 in) and compression ratio rating is 9.8:1. The Nissan VQ23DE motor has two compression and one oil control rings. The connecting rod’s length are 149.8 mm (5.9 in)

Cylinder head

The cylinder head is made of strong, light aluminum alloy which gives it good cooling efficiency. The engine is equipped with hydraulically actuated CVTC (Continuous Variable Valve Timing Control) for intake cams. The camshafts are driven by single primary and two secondary chains. The primary timing chain transmits the rotational movement from the crankshaft to the intake camshafts, the secondary chains connects intake and exhaust sprocket on each head respectively.

The intake valve diameter is 34.0 mm (1.339 in), intake duration is 230°, and the exhaust valve diameter is 29.0 mm (1.142 in), exhaust duration is 232°. The VQ23DE motor does not have hydraulic lifters, so special valve lifters are used to adjust the valve clearance.

Head tightening procedure and torque specs:

• Step 1: 98 Nm; 10.0 kg·m; 72 ft·lb
• Step 2: Loosen all bolts completely
• Step 3: 39.2 kg·m; 4.0 kg·m; 29 ft·lb
• Step 4: Turn all bolts 90°
• Step 5: Turn all bolts another 90°

Problems and malfunctions

The Nissan VQ23DE is reliable and durable. The engine has three timing chains, their service life is about 150,000 miles of mileage (200,000-250,000 km). The valve clearance needs to be adjusted every 60,000 miles of mileage (90,000 km). The Nissan VQ23DE life expectancy is 200,000 miles of mileage (300,000 km).

Maintenance data

Valve clearance adjustment data

Calculate the thickness of new adjusting valve lifter so valve clearance comes within specified values.

R = Thickness of removed valve lifter
N = Thickness of new valve lifter
M = Measured valve clearance

Intake:
N = R + [M – 0.30 mm (0.012 in)]
Exhaust:
N = R + [M – 0.34 mm (0.013 in)]

Valve lifters are available in 27 sizes from 6.66 mm (0.2622 in) to 7.18 mm (0.2827 in), in steps of 0.02 mm (0.0008 in).

Example (exhaust valve):
R = 6.90 mm
M = 0.52 mm
N = 6.90 + (0.52 – 0.34) = 7.08 mm, so we need a valve lifter with identification mark 708U.

Vehicle applications

Author: Sergei Wers
About: Co-founder and CEO of a multi-brand auto repair shop (engine repair, chassis repair, body repair and painting) for over 15 years. I have been developing internet sites with technical specifications for more than seven years.