2018-2022 Equinox & Terrain 1.5L Turbo LYX AWD: Problems, Identification, and Used Replacement

Engine Identification: Confirming the 1.5L LYX AWD

The engine used in the 2018–2022 Chevrolet Equinox and GMC Terrain is a 1.5L turbocharged inline 4-cylinder known as the LYX, part of the General Motors Small Gasoline Engine (SGE) family. This specific version was designed only for All-Wheel Drive (AWD) models. Correctly identifying this engine before purchase is critical, as other similar-looking GM engines will not fit or function properly.

Check Your VIN and RPO Codes

The easiest way to confirm you have the correct engine is by checking your vehicle's identification numbers. A proper pre-purchase verification interview with your parts supplier should always include these checks:

• VIN Check: The 8th character of your vehicle's VIN (Vehicle Identification Number) must be a V.
• RPO Code Check: Look for the Service Parts Identification (SPID) label, usually located in the glove box or trunk. On this label, you should find the code LYX for the engine and F48 for the All-Wheel Drive system.
• Visual Check: Confirm your vehicle is AWD by looking for an AWD badge, a rear driveshaft, or an AWD button on the center console.

Key Interchange Differences

This engine is not interchangeable with units from Front-Wheel Drive (FWD) models or other GM vehicles that use a 1.5L engine, such as the Chevrolet Malibu (LFV engine) or Buick Encore (LE2 engine) due to differences in mounting, wiring, and calibrations.

Common Failure Symptoms

A failing 1.5L LYX engine can present several distinct symptoms. If you experience these, a thorough diagnosis is necessary to confirm if the engine assembly needs replacement.

• Engine Knocking or Ticking: This can indicate severe internal damage, such as cracked pistons from Low-Speed Pre-Ignition (LSPI) or damage from a failed vacuum pump.
• Loss of Power or No-Start Condition: A seized camshaft-driven vacuum pump can damage the exhaust camshaft, leading to incorrect timing and preventing the engine from starting.
• Increased Brake Pedal Effort: The vacuum pump assists the power brakes. If it fails, you may notice the brake pedal becomes much harder to press.
• Excessive Oil Consumption or External Leaks: Clogged PCV (Positive Crankcase Ventilation) system components can cause high pressure inside the engine, forcing oil past the crankshaft seals. Cracked pistons can also lead to burning oil.
• Misfire Codes (P0300-P0304): While many issues can cause misfires, on this engine it can be a sign of cracked spark plug ceramics or, more seriously, piston damage.

Diagnostic Flowchart

Known Problems, Recalls, and Technical Service Bulletins (TSBs)

This engine has several well-documented issues. Always check if these have been addressed on a used engine or if your vehicle has an open recall.

Repair or Replace?

When facing major engine trouble, deciding whether to repair your current engine or replace it with a used unit comes down to the severity of the failure and the cost of parts and labor.

• When Repair Makes Sense: If the camshaft-driven vacuum pump has failed but has NOT seized or sent metal debris through the engine, repair is viable. A dealer replacement was quoted at $1,500, while an independent shop charged another owner $281. If the high-pressure fuel pump is leaking externally but hasn't caused a fire or internal damage, replacement is straightforward and typically costs $728 to $932. A simple external PCV valve replacement can be inexpensive ($88 to $120).
• When Replacement is Smarter: The engine needs to be replaced if it has suffered catastrophic internal failure. Repairing cracked pistons (due to LSPI) can cost between $7,000 and $10,000, often exceeding the value of the vehicle. If a seized vacuum pump destroyed the camshaft and sent metal shavings through the oil, or if the timing chain failed and bent the valves, a used engine replacement is the more economical choice. Furthermore, if PCV system failure requires replacing the valve cover and plastic components break and fall into the cylinder head, one owner was quoted over $4,000 for the repair, making a full engine swap a better value.

Used Engine Replacement Cost

The cost of replacing a 1.5L LYX engine varies based on the type of replacement unit and local labor rates. The provided labor estimate of 12 to 15 hours is for the engine swap itself and does not include diagnostic time or transferring external components.

What Fails at Every Mileage Band

Under 60,000 Miles

Even low-mileage engines can suffer from sudden camshaft-driven mechanical vacuum pump failure, leading to a sudden loss of brake assist and potential engine damage. Cracked pistons from LSPI can also occur early if the wrong oil was used. Turbocharger wastegate solenoids may fail, and cold-climate charge air cooler freezing is a risk.

• ✓Do during install (required): Replace the high-pressure fuel line and all torque-to-yield (TTY) bolts.
• ✓Do during install (recommended): Install a brand new OEM vacuum pump, regardless of the mileage of the replacement engine. The risk of the old pump failing and destroying the new engine is too high.
• ✓Do during install (recommended): Perform a thorough cleaning of the charge air cooler (intercooler) and all associated piping to remove any pooled oil or moisture.
• ✓Cheap insurance while the engine is out: Inspect and clean PCV system components. Service the transmission fluid (many owners report smoother operation when serviced between 40,000-60,000 miles).

60,000 - 100,000 Miles

Vacuum pump failure remains a significant risk. The PCV orifice can clog, leading to high crankcase pressure and blown rear main seals. Carbon buildup on the intake valves becomes more prominent, potentially causing rough idle or misfires. Radiator leaks have also been reported in this band.

• ✓Do during install (required): Replace the high-pressure fuel line, all TTY bolts, and install a new vacuum pump.
• ✓Do during install (recommended): Replace the spark plugs with new OEM iridium plugs. Perform an intake valve decarbonizing service (walnut blasting) while the engine is out and accessible. Replace the thermostat and gasket.
• ✓Cheap insurance while the engine is out: Service the AWD system, including changing the transfer case (PTU) and rear differential fluid.

100,000 - 150,000 Miles

The turbocharger itself may require replacement in this range. While the timing chain is generally considered durable if oil changes are frequent, issues can arise if maintenance was deferred. Repeated vacuum pump failures are possible if the pump wasn't replaced proactively.

• ✓Do during install (required): Replace the high-pressure fuel line, all TTY bolts, and install a new vacuum pump.
• ✓Do during install (recommended): Replace the water pump. Replace all accessible seals and gaskets, such as the front and rear crankshaft seals. Thoroughly inspect the turbocharger being transferred from the old engine for shaft play, and replace oil and coolant lines.
• ✓Cheap insurance while the engine is out: Inspect the timing chain, guides, and tensioner for wear and consider replacement.

Over 150,000 Miles

Owner reports suggest the 1.5L LYX engine can reliably exceed 150,000 miles and potentially reach 200,000-250,000 miles, but this is highly conditional on meticulous maintenance (oil changes every 3,000 to 5,000 miles). At this mileage, failures are related to overall wear, and turbocharger replacement is highly likely.

• ✓Do during install (required): Replace the high-pressure fuel line, all TTY bolts, and install a new vacuum pump.
• ✓Do during install (recommended): A buyer should strongly consider using a lower-mileage engine rather than a high-mileage one, as the cost of preventative parts replacement during installation can become significant. If transferring the turbocharger, a full rebuild or replacement is a wise investment.
• ✓Cheap insurance while the engine is out: Replace the timing chain, water pump, and all major seals.

Real Owner Experiences

Installation: Critical Steps & Common Mistakes

Installing a used 1.5L LYX engine is an advanced to expert-level job. Several unique steps are required to prevent immediate damage to the replacement engine or vehicle.

Required Parts & Fluids for the Swap

Always install the following new parts and fluids during an engine swap to ensure reliability:

• Oil & Filter: 5.3 quarts (5.0 liters) of full synthetic SAE 0W-20 or 5W-30 oil that is dexos1 Gen 2 or Gen 3 certified, plus an ACDelco PF64 filter or equivalent.
• Coolant: GM-approved Dex-Cool antifreeze (50/50 pre-mix).
• Gaskets & Seals: Intake manifold gasket, exhaust manifold gasket, turbocharger gaskets, thermostat housing gasket, vacuum pump seal/gasket, and new front and rear crankshaft seals.
• Fuel System Parts: A new GM high-pressure fuel line is mandatory, as it is a one-time-use crush-seal design. Also, replace the high-pressure fuel pump O-ring.
• Hardware: Torque-to-Yield (TTY) bolts for the harmonic balancer, flywheel/flexplate, and camshaft sprocket must be replaced.
• Ignition: New OEM iridium spark plugs (pre-gapped).

Installation Gotchas & Pro Tips

• Vacuum Pump Inspection: If the original engine failed because the vacuum pump seized, you must install a brand-new vacuum pump on the replacement engine. Do not reuse the old one, as bolting on a failing vacuum pump can immediately destroy the replacement engine's camshaft.
• AWD Transfer Case (PTU) Alignment: The PTU must be carefully aligned and bolted to the structural upper aluminum oil pan to prevent spline damage or severe vibrations.
• PCV System Brittleness: The plastic PCV tubes and connectors become very brittle with age. Handle them with care and expect to replace any that crack or break during the swap.
• Turbocharger Transfer: Damaging oil/coolant lines or failing to use new gaskets during transfer leads to leaks and turbo failure.

Special Tools & Programming

A successful installation requires specific tools and software procedures that cannot be skipped.

• Specialty Tools: You will need a camshaft holding/alignment tool (GM EN-51367), a fuel injector remover/installer tool (GM EN-51146), high-pressure fuel line quick-disconnect tools, and a smoke machine (GE-52250) to check for vacuum leaks.
• Mandatory Programming: After the engine is installed, a Crankshaft Position (CKP) System Variation Relearn procedure must be performed with a GM-compatible diagnostic scan tool (such as an MDI 2 with GDS2 software). If this step is skipped, the engine will run poorly, trigger immediate misfire codes, and often lead the buyer to mistakenly think the replacement engine is bad. Immobilizer/Security Relearn and ECM/PCM Programming updates are also highly recommended.

Questions to Ask Your Installer

Before handing over the keys, ask your mechanic these questions to ensure the job is done right:

• Have you confirmed this is an AWD-specific (LYX, VIN V) engine with the correct structural oil pan?
• Will you be installing a brand-new, one-time-use high-pressure fuel line?
• Will you be replacing all torque-to-yield (TTY) bolts, including those for the harmonic balancer and flexplate?
• Will you be installing a brand-new vacuum pump and inspecting the camshaft for wear?
• Do you have the GM-specific scan tool (GDS2) required to perform the mandatory Crankshaft Position (CKP) System Variation Relearn procedure after installation?
• Will you inspect the charge air cooler and piping for pooled oil or moisture and clean it before startup?
• Have you verified the start/stop accumulator bolts on the transmission are present and correctly torqued per recall 20V668000?
• What brand and viscosity of dexos1 certified full synthetic oil will you be using for the initial fill?

Freight, Delivery, and Pre-Purchase Verification

When ordering a used 1.5L LYX engine assembly, it is important to understand how it will arrive. This is a heavy industrial part, not a standard parcel.

• Shipping Dimensions and Weight: A verified, un-crated 1.5L LYX engine assembly weighs approximately 267 lbs and measures roughly 32" x 33" x 29".
• Freight Delivery: Because of its size and weight, the engine will ship as LTL (Less Than Truckload) freight on a wooden pallet. It will arrive via a large freight truck.
• Liftgate Service: If you are having the engine delivered to a residential address or a shop without a loading dock or forklift, you must request liftgate service so the driver can safely lower the pallet to the ground.
• Inspect Before Signing: Always inspect the engine while it is still on the pallet and the driver is present. Check for any damage to the structural aluminum oil pan, plastic valve covers, or sensors that may have occurred during transit. Do not sign the delivery receipt until you have verified the engine's condition.

Before the First Start: Fluids and Priming

When installing a used engine, you must protect the internal parts from starting dry. A dry start can instantly ruin the engine. Always use fresh fluids and prime the oil system before letting the engine run.

Mandatory Fluids

• Engine Oil: You must use fresh 0W-20 full synthetic oil that meets the GM dexos1 Gen 2 (or newer Gen 3) standard. Do not reuse old oil. Install a brand-new, high-quality oil filter.
• Engine Coolant: Use only fresh Dex-Cool (orange) antifreeze mixed 50/50 with clean water. Using the wrong coolant can cause sludge and ruin the water pump.

Oil Priming Procedure

Priming means pumping oil through the engine before it actually starts and runs. This coats the moving parts with oil to prevent damage.

1. Fill the fluids: Fill the engine with the correct amount of oil and fill the cooling system.
2. Disable the fuel system: Remove the fuel pump fuse or relay. This stops fuel from spraying into the engine so it will not start.
3. Crank the engine: Turn the key to the "Start" position and let the starter motor spin the engine for 10 to 15 seconds.
4. Wait and repeat: Let the starter cool down for one minute. Then, crank the engine again for another 10 to 15 seconds. Watch the dashboard for the low oil pressure warning light to turn off, which means oil is flowing.
5. Start the engine: Put the fuel pump fuse or relay back in. Start the engine normally and let it idle (run slowly without pressing the gas pedal).
6. Check for leaks: Look under the vehicle and around the engine for any dripping oil or coolant. Check the oil dipstick to make sure the level is correct.

Long Block vs. Complete Assembly

When shopping for a used 1.5L LYX engine, you will usually see two choices: a long block or a complete assembly. It is important to know exactly what you are buying.

• Long Block: This includes the core engine parts. You get the engine block, cylinder head, internal moving parts, valve cover, and the special AWD oil pan. It does not include bolt-on accessories.
• Complete Assembly: This includes the long block plus extra parts. It usually comes with the turbocharger, intake and exhaust manifolds, and the high-pressure fuel pump.

Most used LYX engines are sold as long blocks. This means you will need to swap your original turbocharger, alternator, and manifolds over to the replacement engine. Always ask the seller exactly which parts are left on the engine before you buy.

Frequently Asked Questions (FAQ)