Common in older engines; may be due to worn gaskets or seals.

Could be caused by a failing water pump, thermostat, or clogged radiator.

In-Line engines with timing belts need regular replacement to avoid engine damage.

Often due to faulty spark plugs, ignition coils, or fuel injectors, especially in higher mileage vehicles.

Can result from a dirty air filter, bad oxygen sensor, or issues with the fuel injection system.

May be caused by poor quality fuel, carbon buildup, or worn engine bearings.

Could be due to a dirty throttle body, bad idle air control valve, or vacuum leaks.

Various sensor or emission system failures can trigger this warning light.

Hydraulic brake systems can develop leaks in the brake lines, calipers, or master cylinder, leading to reduced braking efficiency.

A spongy or soft brake pedal can indicate air in the hydraulic lines or a failing master cylinder.

Prolonged use of the brakes, especially under heavy load or during towing, can cause the brakes to overheat and lose effectiveness.

With an in-line 6-cylinder engine, misfires could be due to issues with the spark plugs, ignition coils, or fuel injectors.

The electronic fuel injection system can develop issues such as clogged injectors or faulty sensors, leading to poor engine performance.

Older engines like the 1991 Ford F-150's in-line 6 can suffer from radiator, water pump, or thermostat failures, causing overheating.

Over time, the timing chain can stretch or wear out, leading to poor engine timing and performance issues.

Common in older engines, oil leaks can occur from the valve cover gasket, oil pan, or rear main seal.

Vacuum hoses can become brittle and crack over time, causing rough idling and poor engine performance.

The exhaust manifold can develop cracks, leading to exhaust leaks and reduced engine performance.

The Exhaust Gas Recirculation (EGR) valve can become clogged or fail, affecting emissions and engine performance.

Common in older engines, and the 5M-GE is no exception. Gaskets and seals can wear out, leading to oil leaks.

This can be caused by a failing radiator, water pump, or thermostat. In older models, clogged or corroded coolant passages can also be an issue.

The 5M-GE engine uses a timing belt that needs regular replacement. If not maintained, it can break and cause significant engine damage.

With electronic fuel injection, clogged or failing fuel injectors can lead to poor performance and reduced fuel efficiency.

Old hoses and gaskets can develop leaks, leading to rough idling and poor engine performance.

Older engines like the 5M-GE may suffer from head gasket issues, leading to coolant and oil mixing, overheating, and poor performance.

Worn out spark plugs, ignition wires, and distributor components can cause misfires and poor engine performance.

The electronic fuel injection system relies on various sensors (e.g., oxygen sensor, throttle position sensor). Failure of these sensors can lead to poor engine performance and increased emissions.

The Toyota 5M-GE engine can be prone to overheating issues, often due to a failing radiator, water pump, or thermostat.

Due to the age of the vehicle, the head gasket may fail, leading to coolant and oil mixing, which can cause severe engine damage.

The complex vacuum lines in the 5M-GE engine can develop leaks over time, causing rough idling and poor performance.

Faulty spark plugs, ignition wires, or distributor issues can lead to misfires and reduced engine performance.

As the engine uses an electronic fuel injection system, problems with fuel injectors, sensors, or the ECU can lead to poor fuel economy and engine performance.

Over time, the timing chain can stretch or wear out, leading to poor engine timing and performance issues.

Commonly, valve cover gaskets and oil pan gaskets may wear out and cause oil leaks.

The Exhaust Gas Recirculation (EGR) valve can become clogged or fail, leading to increased emissions and engine performance issues.

Turbocharged engines like the one in the 1991 Ford Probe can experience oil leaks due to increased pressure and heat, which can cause seals and gaskets to fail.

The turbocharger can wear out over time due to high operating temperatures and pressures, leading to reduced performance or failure.

EFI systems can develop problems with sensors, injectors, or the control module, leading to poor engine performance or starting issues.

Turbocharged and intercooled engines can be prone to overheating if the cooling system is not well-maintained or if there is a failure in the intercooler.

High pressures from turbocharging can cause head gasket failure, leading to coolant and oil mixing or loss of compression.

In-line 4-cylinder engines can experience wear in the timing belt or chain, which could lead to timing issues or engine damage if not replaced at recommended intervals.

Components like spark plugs, ignition coils, and wires can wear out, causing misfires or poor engine performance.

Turbocharged engines have complex vacuum systems that can develop leaks, leading to poor engine performance and fuel efficiency.

The intercooler can become clogged or damaged, reducing its effectiveness and potentially leading to engine overheating or loss of power.

Common in older engines; may be due to worn gaskets or seals.

Could be caused by a failing water pump, thermostat, or clogged radiator.

In-Line engines with timing belts need regular replacement to avoid engine damage.

Often due to faulty spark plugs, ignition coils, or fuel injectors, especially in higher mileage vehicles.

Can result from a dirty air filter, bad oxygen sensor, or issues with the fuel injection system.

May be caused by poor quality fuel, carbon buildup, or worn engine bearings.

Could be due to a dirty throttle body, bad idle air control valve, or vacuum leaks.

Various sensor or emission system failures can trigger this warning light.

Common in older engines, especially around the valve cover gasket, oil pan gasket, and front and rear crankshaft seals.

Can be caused by a failing thermostat, clogged radiator, or malfunctioning water pump.

Faulty spark plugs, ignition wires, or ignition coils can lead to misfires and poor engine performance.

Issues with the electronic fuel injection system can lead to poor fuel economy and engine performance.

Can cause rough idling, stalling, and poor fuel economy. Common areas include intake manifold gaskets and vacuum hoses.

A worn or broken timing belt can cause severe engine damage. It's crucial to replace it at recommended intervals.

Faulty oxygen sensors or mass air flow sensors can cause rough running and check engine light activation.

A clogged or malfunctioning EGR valve can cause performance issues and increased emissions.

Can cause excessive engine vibration and noise.

Aging gaskets and seals on a 1984 engine can lead to oil leaks, especially around the valve cover and oil pan.

The turbocharger can wear out over time, leading to reduced performance or complete failure.

Electronic Fuel Injection (EFI) systems from the 1980s can develop issues with sensors, wiring, or injectors, affecting engine performance.

Older engines can suffer from cooling system issues, such as a failing radiator, water pump, or thermostat.

Timing chains or belts can wear out, causing engine misfires or failure.

Aging hoses and gaskets can develop vacuum leaks, leading to rough idling and poor fuel economy.

Components like the distributor, spark plugs, and ignition coils can wear out, causing misfires and starting issues.

Over time, exhaust components such as the manifold, pipes, and muffler can corrode, leading to leaks and increased emissions.

Older electronic systems can suffer from sensor failures, affecting engine management and performance.

Hydraulic brake systems rely on brake fluid to function. Leaks can lead to decreased braking power or complete brake failure.

The master cylinder generates the hydraulic pressure needed for braking. A failure can result in a spongy brake pedal or loss of braking power.

Over time, brake pads wear down and need to be replaced to maintain effective braking.

Excessive heat can cause the brake rotors to warp, leading to vibrations or pulsations when braking.

The vacuum booster helps reduce the effort needed to apply the brakes. If it fails, braking can become more difficult.

In-line engines can sometimes have cooling issues, leading to overheating, which can cause significant engine damage.

Older engines, like the one in the 1985 Ford Bronco, are prone to developing oil leaks, which can lead to low oil levels and engine damage.

Problems with the ignition system can lead to misfires, poor performance, and difficulty starting the engine.

Given the vehicle's age, it likely has a carburetor, which can become clogged or out of adjustment, leading to poor engine performance.

The exhaust manifold can develop cracks over time, leading to exhaust leaks and reduced engine efficiency.

The timing chain can stretch or wear out over time, leading to poor engine timing and performance issues.

An older fuel pump can fail, causing the engine to sputter or stall.

Older vehicles like the 1985 Ford Bronco can experience problems with the transmission, such as slipping or difficulty shifting gears.

Common in older engines, and the 5M-GE is no exception. Gaskets and seals can wear out, leading to oil leaks.

This can be caused by a failing radiator, water pump, or thermostat. In older models, clogged or corroded coolant passages can also be an issue.

The 5M-GE engine uses a timing belt that needs regular replacement. If not maintained, it can break and cause significant engine damage.

With electronic fuel injection, clogged or failing fuel injectors can lead to poor performance and reduced fuel efficiency.

Old hoses and gaskets can develop leaks, leading to rough idling and poor engine performance.

Older engines like the 5M-GE may suffer from head gasket issues, leading to coolant and oil mixing, overheating, and poor performance.

Worn out spark plugs, ignition wires, and distributor components can cause misfires and poor engine performance.

The electronic fuel injection system relies on various sensors (e.g., oxygen sensor, throttle position sensor). Failure of these sensors can lead to poor engine performance and increased emissions.

Hydraulic brake systems can develop leaks in brake lines, master cylinder, or wheel cylinders, leading to decreased braking performance.

Air can enter the hydraulic lines, causing a soft or spongy brake pedal feel, which reduces braking efficiency.

Over time, brake rotors can warp due to excessive heat, leading to vibrations or pulsations when braking.

Brake calipers can seize or stick, causing uneven wear on brake pads and reduced braking performance.

Issues with the brake master cylinder or brake booster can lead to low brake pedal pressure, compromising braking effectiveness.

Electronic fuel injection systems can suffer from clogged injectors, leading to poor engine performance and reduced fuel efficiency.

Problems with the ignition system, such as faulty spark plugs or ignition coils, can cause engine misfires, reducing engine performance.

Vacuum leaks in the intake system can lead to rough idling, poor acceleration, and overall decreased engine performance.

The cooling system can develop issues, such as a faulty thermostat or radiator, leading to engine overheating.

A worn or stretched timing chain/belt can lead to poor engine performance and potential engine damage if not addressed.

Common in older engines, oil leaks can occur from gaskets, seals, or the oil pan, leading to reduced oil levels and potential engine damage.

A failing fuel pump can cause inconsistent fuel delivery, leading to engine stalling or difficulty starting.

Malfunctioning oxygen sensors can lead to incorrect air-fuel mixture adjustments, reducing engine efficiency and increasing emissions.

Due to the age of the vehicle, gaskets and seals can deteriorate, leading to oil leaks.

The timing belt in this engine needs regular replacement; failure can cause severe engine damage.

Overheating or poor maintenance can lead to head gasket failure, causing coolant and oil to mix.

Older engines can experience wear in the valve train components, leading to reduced performance and noise.

Clogged or malfunctioning fuel injectors can lead to poor engine performance and reduced fuel efficiency.

Worn-out spark plugs, ignition wires, and distributor components can cause misfires and starting issues.

Radiator, hoses, and water pump may develop leaks, leading to overheating problems.

The Exhaust Gas Recirculation (EGR) valve can become clogged, affecting engine performance and emissions.

Hydraulic brake systems can develop leaks in the brake lines, master cylinder, or wheel cylinders, leading to decreased braking performance and potential brake failure.

Overheating of brake components due to heavy use can cause brake fade, where the brakes become less effective.

Brake pads wear down over time and need regular replacement to maintain effective braking.

The electronic fuel injection system can have problems such as clogged fuel injectors, faulty sensors, or issues with the electronic control unit (ECU).

Common in older vehicles, overheating can be caused by issues such as a failing water pump, radiator problems, or a malfunctioning thermostat.

Engine oil leaks can occur from the valve cover gaskets, oil pan gasket, or rear main seal, leading to low oil levels and potential engine damage.

The timing chain or belt can wear out or become misaligned, leading to engine performance issues or severe engine damage if it fails.

Problems with the ignition coil, distributor, or spark plugs can cause misfires, poor engine performance, and difficulty starting the engine.

Exhaust manifold leaks can cause a ticking noise and may result in decreased engine performance and increased emissions.

A failing fuel pump can lead to poor fuel delivery to the engine, resulting in stalling, difficulty starting, or poor performance.

A malfunctioning TPS can cause erratic idling, stalling, or poor acceleration.

A dirty or failing MAF sensor can cause incorrect air-fuel mixture readings, leading to poor engine performance and fuel efficiency.

Faulty oxygen sensors can cause the engine to run too rich or too lean, affecting emissions and fuel economy.

Hydraulic brake systems can develop leaks in the brake lines, hoses, or master cylinder, leading to reduced braking efficiency.

Overheating of brake components due to excessive use can cause a temporary loss of braking power.

Air trapped in the hydraulic brake lines can cause the brake pedal to feel spongy and reduce braking effectiveness.

Brake pads wear down over time and need to be replaced to maintain proper braking performance.

The master cylinder can fail, causing a loss of hydraulic pressure and brake function.

Older engines, like the 1986 Ford F-150, may develop oil leaks around seals and gaskets.

Problems with the electronic fuel injection system, such as clogged injectors or faulty sensors, can lead to poor engine performance.

Worn spark plugs, faulty ignition coils, or distributor issues can cause misfires and poor engine performance.

Cooling system issues, such as a failing water pump, radiator leaks, or a faulty thermostat, can cause the engine to overheat.

Vacuum leaks in the intake manifold or vacuum hoses can lead to rough idling and poor fuel economy.

Wear and tear on the timing chain or belt can cause engine timing issues, leading to poor performance or engine failure.

Leaks in the exhaust system can cause increased noise, reduced performance, and potential safety hazards from exhaust fumes.

Hydraulic brake systems can develop leaks in the brake lines, calipers, or master cylinder, leading to reduced braking efficiency.

A spongy or soft brake pedal can indicate air in the hydraulic lines or a failing master cylinder.

Prolonged use of the brakes, especially under heavy load or during towing, can cause the brakes to overheat and lose effectiveness.

With an in-line 6-cylinder engine, misfires could be due to issues with the spark plugs, ignition coils, or fuel injectors.

The electronic fuel injection system can develop issues such as clogged injectors or faulty sensors, leading to poor engine performance.

Older engines like the 1991 Ford F-150's in-line 6 can suffer from radiator, water pump, or thermostat failures, causing overheating.

Over time, the timing chain can stretch or wear out, leading to poor engine timing and performance issues.

Common in older engines, oil leaks can occur from the valve cover gasket, oil pan, or rear main seal.

Vacuum hoses can become brittle and crack over time, causing rough idling and poor engine performance.

The exhaust manifold can develop cracks, leading to exhaust leaks and reduced engine performance.

The Exhaust Gas Recirculation (EGR) valve can become clogged or fail, affecting emissions and engine performance.

The 5M-GE engine, like many older engines, may have cooling system issues such as a failing thermostat, water pump, or clogged radiator, which can lead to overheating.

Gaskets and seals in older engines like the 5M-GE can deteriorate over time, leading to oil leaks, particularly from the valve cover gasket, oil pan gasket, and rear main seal.

The electronic fuel injection system can suffer from clogged or malfunctioning fuel injectors, leading to poor engine performance and reduced fuel efficiency.

The 5M-GE engine uses a timing belt that can wear out and may need regular replacement to avoid engine damage.

Problems with the ignition system, such as worn-out spark plugs, distributor cap, and rotor, can cause misfires and poor engine performance.

Vacuum hoses and connections can become brittle and crack over time, leading to vacuum leaks that can cause rough idling and poor acceleration.

An older engine like the 5M-GE may develop head gasket issues, leading to coolant mixing with oil or compression loss between cylinders.

The Exhaust Gas Recirculation (EGR) valve can become clogged or fail, causing increased emissions and poor engine performance.

Various sensors, including the oxygen sensor, coolant temperature sensor, and mass air flow sensor, can fail or provide inaccurate readings, leading to engine performance issues.

Common in older engines, often due to worn gaskets or seals.

Can wear out or break, leading to engine damage if not replaced according to schedule.

Turbocharged engines can suffer from turbo lag, wear, and eventual failure.

EFI systems can have clogged or malfunctioning fuel injectors, affecting performance.

Turbocharged engines are prone to head gasket issues due to higher pressures.

Problems with spark plugs, ignition coils, or distributor can cause misfires and poor performance.

Turbocharged engines generate more heat, leading to potential overheating if the cooling system is not maintained.

Can occur in the intake manifold or related hoses, causing rough idling and poor performance.

EFI systems rely on various sensors (like the oxygen sensor) that can fail over time, affecting fuel efficiency and emissions.