Maintaining the 1987 Isuzu Impulse 1.9L requires specific attention to lubrication to ensure longevity and smooth operation. As this vehicle approaches its fourth decade of service, the engine internals and transmission systems face the challenges of age, including potential wear, oil consumption, and the need for superior cleaning capabilities to remove decades of sludge and varnish. Using the correct viscosity and formulation can make a significant difference in preserving performance and reliability on the road today.
Recommended AMSOIL Products
- AMSOIL Signature Series 5W-30 100% Synthetic Motor Oil – The top-tier choice for maximum protection against wear, extending up to 25,000 miles or one year, ideal for high-mileage Isuzus seeking superior horsepower retention.
- AMSOIL Extended-Life 5W-30 100% Synthetic Motor Oil – A robust option that offers 37% more cleaning power than standard options, helping to keep older engines running smoother for up to 20,000 miles between changes.
- AMSOIL OE 5W-30 100% Synthetic Motor Oil – Engineered to outperform conventional oils with a 100% synthetic formulation that fights sludge and deposits effectively.
- AMSOIL 5W-30 100% Synthetic High-Mileage Motor Oil – Specifically formulated for vehicles with over 75,000 miles, featuring enhanced additives to reduce sludge by 67% and improve oil consumption control.
- WIX Oil Filter – A premium filtration partner that offers improvements over original equipment manufacturer-branded filters to ensure clean oil circulation.
- AMSOIL Passenger Car & Light Truck Antifreeze & Coolant – A 50/50 pre-mix formula that protects cooling system metals, gaskets, and hoses for up to 150,000 miles or 5 years.
- AMSOIL Propylene Glycol Antifreeze and Engine Coolant – A concentrated option requiring mixing, offering exceptional corrosion protection for up to 150,000 miles in passenger cars.
- AMSOIL Signature Series Multi-Vehicle 100% Synthetic Automatic Transmission Fluid – Withstands heavy towing and elevated temperatures, remaining fluid in sub-zero conditions.
- AMSOIL OE Multi-Vehicle 100% Synthetic Automatic Transmission Fluid – Provides excellent cold-weather performance, guards against leaks, and promotes smooth, shudder-free shifts.
- AMSOIL DOT 3 and DOT 4 100% Synthetic Brake Fluid – Delivers excellent ABS and traction-control responsiveness with a stable viscosity over a wide temperature range.
- AMSOIL SEVERE GEAR® 80W-90 100% Synthetic Gear Lube – Provides advanced protection against wear and helps reduce operating temperatures in the differential.
- AMSOIL SEVERE GEAR® 75W-90 100% Synthetic Gear Lube – A versatile option that controls thermal runaway and extends the life of oil seals and equipment.
- AMSOIL SEVERE GEAR® 75W-110 100% Synthetic Gear Lube – Ideal for heavier loads, offering long-lasting protection against rust and corrosion.
The 1987 Isuzu Impulse with the 1.9L engine code [A] A was a compact sport coupe that blended performance with fuel efficiency, a combination that was quite appealing in the late 1980s. The power plant of choice, a 1.9-liter inline-four, produced a respectable amount of horsepower for its displacement, allowing the lightweight vehicle to accelerate with confidence. Owners often praised the Impulse for its nimble handling, which was a direct result of the chassis tuning designed to complement the agile engine. This model year represents a time when Japanese automakers were beginning to assert their dominance in the import market, offering reliability and innovation that challenged established American and European rivals.
Despite its enduring appeal, this vehicle does have some maintenance considerations that owners should be aware of. The rubber components, such as seals and hoses, have had decades to age, which can lead to minor leaks if not monitored. Additionally, as the engine has accumulated significant miles, piston ring wear can become a factor, potentially leading to oil consumption or a loss of compression. Using a high-mileage synthetic oil is an excellent preventative measure to help mitigate these aging effects by maintaining a protective film on metal surfaces. Another common area of concern for these older Impulses is the cooling system; the original radiator and plastic end tanks are subject to heat fatigue over time, making the use of a high-quality antifreeze like AMSOIL vital to prevent overheating and corrosion.
Perhaps one of the most critical maintenance points for the 1987 Impulse is the clutch and transmission synchronization. The manual transmission in these cars can become notchy or experience grinding as the synchros wear down. Shifting into a synthetic motor oil for manual gearboxes or utilizing the Extended-Life formulation can reduce the friction required for smooth engagement. The rear differential is another component that benefits from regular flushing, as the gear lube degrades over time and loses its ability to protect the limited-slip mechanisms. By staying on top of these fluid exchanges, owners can significantly extend the usable life of the vehicle.
Beyond the drivetrain, the electrical system on these coupes can be sensitive to voltage spikes and moisture intrusion, though this is less related to lubrication. However, using a fuel additive like AMSOIL P.i. Performance Improver can help clean the fuel injectors, which may have accumulated carbon deposits over the years. This restoration of injector flow can improve engine smoothness and restore lost horsepower. For those who keep their vehicles in storage during winter months, using an engine fogging oil is essential to prevent internal rusting of the cylinder walls while the car is sitting idle.
The 1987 Isuzu Impulse remains a beloved classic for enthusiasts who appreciate a blend of sporty styling and practical reliability. With the right maintenance schedule and premium lubricants, this vehicle can continue to provide a fun and safe driving experience. Whether you are a weekend driver or a dedicated restorer, ensuring the engine, transmission, and differential are properly serviced with high-performance fluids will keep this classic running as it did when it rolled off the line decades ago.
Proper lubrication is not just about keeping an engine running; it is about preserving the vehicle’s integrity against the inevitable effects of time. The synthetic formulations available today offer a level of protection that was not present in the original factory fill. By selecting the appropriate AMSOIL Signature Series products for your 1987 Isuzu Impulse, you are investing in the continued health of your vehicle, ensuring that it remains a reliable companion on the road for years to come.
About the Vehicle
The 1987 Isuzu Impulse was a standout in the compact sports coupe segment, known for its sleek, aerodynamic design that looked far more modern than many of its contemporaries. Produced by Isuzu Motors, the Impulse was distinct for its two-door body style and a reputation for being a capable daily driver that didn’t sacrifice style for utility. The 1.9L engine, often designated as the [A] code, was a fuel-injected inline-four that provided a good balance of power and economy, making it suitable for both city commuting and longer highway drives.
Owners of this vehicle often cite its handling characteristics as a major highlight. The suspension was tuned to provide a firm but compliant ride, allowing the car to take corners with confidence. This agility made the Impulse a favorite among driving enthusiasts who valued a responsive steering feel and a chassis that communicated well with the driver. The interior, while typical for its era, offered a driver-focused cockpit that was comfortable and functional, with controls laid out for easy access.
There are a few known issues that owners of the 1987 Impulse should be vigilant about. One common problem is the failure of the crankshaft position sensor, which can cause the engine to stall unexpectedly or fail to start. Regular inspection of the electrical connections and replacing this sensor with a reliable aftermarket part can resolve this. Another prevalent issue is the degradation of the fuel vapor canister and related hoses, which can lead to rough idling or stalling. This can be mitigated by ensuring the fuel system is clean and well-maintained.
Additionally, the water pump on these older models can fail due to the wear of the impeller or the bearing, leading to coolant leaks or overheating. Replacing the water pump with a high-quality unit and flushing the cooling system thoroughly is a crucial preventive maintenance step. Finally, the clutch release bearing can wear out over time, resulting in a noise when the clutch pedal is depressed. Addressing this early with the right lubricants and timely replacement can prevent damage to the flywheel and pressure plate.
By understanding these characteristics and potential pitfalls, owners can better care for their 1987 Isuzu Impulse. The combination of a robust engine design and a solid chassis makes it a rewarding vehicle to maintain, especially when using high-performance lubricants that offer superior protection against wear and heat. Whether you are restoring one for a show or keeping it for regular use, the right fluids will ensure that the Isuzu Impulse continues to perform with the spirit that made it a classic.