Nissan KA24DE Engine Specs

The Nissan KA24DE engine, a 2.4-liter inline-four, is a workhorse that powered numerous Nissan vehicles from the late 1980s through the early 2000s. Vehicles like the 240SX, Altima, and even the Hardbody pickup relied on this engine's robust design. However, like any engine, the KA24DE is susceptible to wear and tear, and understanding its specifications is crucial for proper maintenance and troubleshooting. Many owners encounter performance issues that, while seemingly minor at first, can escalate into serious problems if left unaddressed. Knowing the specifications – from compression ratios to timing belt intervals – can help you diagnose and repair these problems effectively.

The KA24DE Specs is similar to the KA24E. As the KA24E is SOHC with three valves per cylinder, the KA24DE is DOHC with 4 valves per cylinder and shim-over-bucket valve actuation. Additional feature changes include the use of a knock sensor, oil injection at the base of each piston, and top-firing spark plugs. To gain more power and torque, the KA24DE Engine has a quite wider power band than the KA24E.

Nissan KA24DE Specs

Nissan KA24DE Horsepower

The ka24de power is rated 140 hp / 160 tq?

KA24DE engines also have been proven beyond doubt to be absolutely tough. In turbocharged form with stock long block 500+ whp has been achieved but short lived and 1000+ whp fully built. There are a plethora of stock block 300+ whp daily driven KA24DE-T’s. This Nissan KA engine has pushed into the 7 seconds in the 1/4 mile in some Nissan 240SX’s.

With their large stroke these Nissan KA24DE Specs engines are known for being low revving torque “monsters” considering the torque numbers have been known to stay with or even higher than hp output.

Car Used KA24DE Engine

• Nissan 240SX
• Nissan Altima
• Nissan Pathfinder
• Nissan Xterra
• Nissan Bassara
• Nissan Bluebird
• Nissan Caravan
• Nissan Hardbody
• Nissan Navara
• Nissan Pintara
• Nissan Prairie
• Nissan Presage
• Nissan R’nessa
• Nissan Serena
• Nissan Stanza
• Nissan Terrano II
• Ford Corsair

Common Problems and Solutions with the KA24DE Engine

Problem: Rough Idle and Stalling

Problem Overview: A rough idle, characterized by erratic engine RPMs at a standstill, or even complete stalling, is a common complaint among KA24DE owners. This issue can affect driveability, fuel economy, and overall engine performance.

Symptoms:

• Unstable RPMs at idle (typically fluctuating below the normal range of 750-850 RPM).
• Engine shaking or vibrating excessively at idle.
• Difficulty starting the engine.
• Stalling at idle, especially when the engine is cold.
• Poor throttle response.
• Check Engine Light (CEL) illuminated, potentially with codes related to fuel trim, idle air control, or misfires.

Root Cause: The root causes of rough idle and stalling in the KA24DE can be varied, but some of the most common include:

• Vacuum Leaks: Avacuum leak allows unmetered air into the engine, disrupting the air-fuel mixture and causing the engine to run lean. This is a very common culprit in older engines with aging rubber hoses and gaskets.
• Dirty or Faulty Idle Air Control (IAC) Valve: The IAC valve regulates the amount of air bypassing the throttle plate at idle, maintaining a stable RPM. A clogged or malfunctioning IAC valve cannot properly control idle speed.
• Clogged Fuel Injectors: Dirty fuel injectors can impede fuel flow, resulting in a lean mixture and rough idle.
• Faulty Mass Air Flow (MAF) Sensor: The MAF sensor measures the amount of air entering the engine. A faulty MAF sensor can provide inaccurate readings to the ECU, leading to incorrect fuel delivery.
• Weak or Failing Ignition Components: Worn spark plugs, faulty ignition wires, or a failing distributor cap and rotor (on older models) can cause misfires and rough idle.
• Low Compression: Worn piston rings or valves can lead to low compression in one or more cylinders, resulting in poor engine performance and rough idle.

What Happens If Ignored: Ignoring a rough idle can lead to:

• Decreased fuel economy.
• Increased emissions.
• Increased engine wear.
• Potential damage to the catalytic converter due to misfires.
• Complete engine failure in extreme cases.

Recommended Fixes:

1. Check for Vacuum Leaks: Inspect all vacuum hoses for cracks, leaks, or disconnections. A common technique is to spray carburetor cleaner around vacuum lines while the engine is running; a change in engine RPM indicates a leak. Replace any damaged hoses or gaskets.
2. Clean or Replace the IAC Valve: Remove the IAC valve and clean it thoroughly with carburetor cleaner. If cleaning doesn't resolve the issue, replace the valve.
3. Clean Fuel Injectors: Use a fuel injector cleaner additive in the fuel tank or have the injectors professionally cleaned. In severe cases, injector replacement may be necessary.
4. Test or Replace the MAF Sensor: Use a multimeter to test the MAF sensor's output. Compare the readings to the manufacturer's specifications. Replace the MAF sensor if it is faulty.
5. Replace Ignition Components: Replace spark plugs, ignition wires, distributor cap, and rotor (if applicable). Ensure the spark plugs are gapped correctly.
6. Perform a Compression Test: Perform a compression test to check for low compression in any cylinders. If low compression is detected, further investigation is needed to determine the cause (worn rings, valves, etc.).

Cost Estimates/Shop Advice: DIY vacuum leak repair can be very inexpensive, costing only the price of new hoses (typically under $20). Cleaning the IAC valve is also relatively inexpensive. Replacing the IAC valve can range from $50 to $150, depending on the brand. Cleaning fuel injectors professionally can cost around $100-$200. MAF sensor replacement can range from $80 to $300. Ignition component replacement can cost $50-$150. A compression test at a shop will typically cost around $50-$100. If you are not comfortable performing these repairs yourself, consult a qualified mechanic. Be sure to ask for an estimate before authorizing any work.

Problem: Overheating

Problem Overview: Overheating is a serious problem that can cause significant engine damage if not addressed promptly. The KA24DE is known for its robustness, but overheating can quickly compromise its integrity.

Symptoms:

• Temperature gauge reading excessively high.
• Steam or coolant escaping from the engine compartment.
• Sweet smell of coolant.
• Engine knocking or pinging.
• Loss of power.
• Check Engine Light (CEL) illuminated, potentially with codes related to engine temperature.

Root Cause: Common causes of overheating in the KA24DE include:

• Low Coolant Level: Insufficient coolant prevents proper heat transfer from the engine.
• Leaking Coolant System: Leaks in the radiator, hoses, water pump, or head gasket can cause coolant loss.
• Faulty Thermostat: A stuck-closed thermostat prevents coolant from circulating through the radiator, leading to overheating.
• Clogged Radiator: A clogged radiator restricts coolant flow and reduces its cooling capacity.
• Faulty Water Pump: A failing water pump cannot circulate coolant effectively.
• Blown Head Gasket: A blown head gasket can allow combustion gases to enter the cooling system, causing overheating.
• Faulty Radiator Fan: If the radiator fan isn't functioning properly, the engine isn't cooled efficiently, especially during low-speed driving or when idling.

What Happens If Ignored: Ignoring overheating can lead to:

• Warped cylinder head.
• Cracked engine block.
• Blown head gasket (if it wasn't the initial cause).
• Complete engine failure.

Recommended Fixes:

1. Check and Top Off Coolant Level: Ensure the coolant level is at the proper level in the radiator and overflow reservoir.
2. Inspect for Coolant Leaks: Carefully inspect all coolant hoses, the radiator, water pump, and head gasket area for leaks. Repair or replace any leaking components. A pressure test of the cooling system can help identify leaks.
3. Replace the Thermostat: Replace the thermostat with a new one of the correct temperature rating.
4. Flush the Radiator: Flush the radiator to remove any debris or sediment that may be clogging it. If the radiator is severely clogged, it may need to be replaced.
5. Replace the Water Pump: If the water pump is suspected of failing, replace it with a new one.
6. Test for a Blown Head Gasket: Perform a block tester test to check for combustion gases in the coolant. If a head gasket leak is detected, the head gasket must be replaced. This is a major repair that requires removing the cylinder head.
7. Check Radiator Fan Operation: Ensure the radiator fan is turning on when the engine reaches operating temperature. Check the fan motor, relay, and temperature sensor.

Cost Estimates/Shop Advice: Adding coolant is inexpensive. Replacing a thermostat is typically under $50 in parts, and labor is usually an hour or less. Flushing the radiator can cost between $80 and $150. Water pump replacement can range from $150 to $400, depending on the water pump's cost and the amount of labor. Head gasket replacement is a major repair that can cost anywhere from $1000 to $2500, depending on the shop and the extent of the damage. Diagnosing the source of overheating can be complex, so it is often best to consult a qualified mechanic to avoid misdiagnosis and unnecessary repairs. Always ask for an estimate upfront.

Problem: Excessive Oil Consumption

Problem Overview: Excessive oil consumption means your KA24DE is burning more oil than normal. This can lead to low oil levels, engine damage, and even catastrophic failure if left unchecked. While some oil consumption is normal, anything beyond about a quart every 1,000 miles is considered excessive.

Symptoms:

• Needing to add oil frequently (more than usual).
• Blue smoke coming from the exhaust.
• Oil leaks under the vehicle.
• Fouled spark plugs.
• Low oil pressure.

Root Cause: The main causes of excessive oil consumption in the KA24DE are:

• Worn Valve Stem Seals: Valve stem seals prevent oil from leaking down the valve stems and into the combustion chamber. Worn seals allow oil to be burned during combustion.
• Worn Piston Rings: Piston rings seal the combustion chamber and prevent oil from entering. Worn rings allow oil to pass into the combustion chamber and be burned.
• Oil Leaks: External oil leaks, such as from the valve cover gasket, oil pan gasket, or rear main seal, can contribute to oil loss.
• PCV Valve Malfunction: A stuck-closed PCV valve can cause excessive pressure in the crankcase, forcing oil past seals and rings.

What Happens If Ignored: Ignoring excessive oil consumption can lead to:

• Damaged catalytic converter.
• Engine knocking and reduced performance.
• Engine seizure due to oil starvation.

Recommended Fixes:

1. Replace Valve Stem Seals: Replacing valve stem seals can be done with the cylinder head on the engine in some cases, but it's often easier with the head removed.
2. Replace Piston Rings: Replacing piston rings requires removing the engine and disassembling it. This is a major repair.
3. Repair Oil Leaks: Replace any leaking gaskets or seals.
4. Replace PCV Valve: Replace the PCV valve with a new one. It's a cheap and easy fix that can often make a difference.
5. Use Higher Viscosity Oil: Switching to a slightly higher viscosity oil (e.g., 10W-40 instead of 5W-30) may help reduce oil consumption, especially in older engines with worn components.

Cost Estimates/Shop Advice: Replacing valve stem seals can range from $500 to $1000. Piston ring replacement can cost $1500 to $3000. Replacing gaskets and seals is relatively inexpensive, typically ranging from $50 to $200 per gasket or seal, plus labor. A new PCV valve is inexpensive, costing under $20. Before undertaking any major repairs, it's wise to have a mechanic perform a thorough inspection to pinpoint the exact cause of the oil consumption. Considering the age of many KA24DE engines, a complete engine rebuild or replacement might be a more cost-effective option in some cases.

Credibility and Additional Notes: It's worth noting that several Technical Service Bulletins (TSBs) were issued over the years addressing various issues with the KA24DE. While many of these TSBs are now outdated, they can provide valuable insight into common problems and recommended solutions. Online forums and communities dedicated to Nissan vehicles are also excellent resources for information and troubleshooting tips. Many KA24DE engines begin to exhibit signs of wear and tear, like increased oil consumption, around the 150,000-mile mark, but proper maintenance can significantly extend their lifespan. Regularly checking your fluid levels and addressing any issues promptly are key to keeping your KA24DE running smoothly.