1990 BMW 735iL

Introduction:

The 1990 BMW 735iL is a luxury sedan known for its impressive performance, sophisticated design, and advanced technology. It comes with a powerful 3.5-liter inline-six engine that produces 208 horsepower and 225 lb-ft of torque. The vehicle is available with a 4-speed automatic transmission. Praised for its handling, comfort, and classic styling, the 735iL does have some common issues that owners should be aware of.

Engine

3.5L Inline-Six

• Head Gasket Failure: Symptoms include white smoke from the exhaust, overheating, and coolant leaks. Solution requires replacing the head gasket and resurfacing the cylinder head. Estimated Cost: $2,500 - $3,500+
• Timing Belt Tensioner Failure: If the timing belt tensioner fails, it can cause the timing belt to slip or break, resulting in catastrophic engine damage. Solution: Replace the timing belt and tensioner. Estimated Cost: $600 - $1,000
• Valve Stem Seal Failure: Worn or damaged valve stem seals can lead to excessive oil consumption and smoking from the exhaust. Solution: Replace the valve stem seals. Estimated Cost: $1,500 - $2,000

Transmission

4-Speed Automatic

• Transmission Fluid Leaks: Leaks can occur from the transmission pan gasket, seals, or lines. Solution: Replace the leaking component and refill the transmission fluid. Estimated Cost: $200 - $500
• Shifting Problems: Difficulty shifting gears or slipping gears can indicate a problem with the transmission control module, solenoids, or other internal components. Solution: May require replacing or repairing various transmission components. Estimated Cost: $1,000 - $3,000+

Suspension

• Strut Mount Failure: Worn or damaged strut mounts can cause clunking or knocking noises when driving over bumps. Solution: Replace the strut mounts. Estimated Cost: $300 - $600
• Control Arm Bushing Failure: Worn or torn control arm bushings can lead to poor handling and stability. Solution: Replace the control arm bushings. Estimated Cost: $200 - $400
• Sway Bar End Link Failure: Loose or damaged sway bar end links can cause rattling or clunking noises when driving. Solution: Replace the sway bar end links. Estimated Cost: $150 - $300

Electrical

• Battery Discharge: Batteries can lose power prematurely due to parasitic drains or electrical component failures. Solution: Test the battery and charging system, and replace or repair faulty components as needed. Estimated Cost: $200 - $600+
• Alternator Failure: A failing alternator can prevent the battery from charging properly, leading to power loss. Solution: Replace the alternator. Estimated Cost: $400 - $700
• Electrical Harness Issues: Wiring harnesses can develop shorts or breaks, causing various electrical problems. Solution: Repair or replace the affected wiring harness. Estimated Cost: $500 - $1,500+

Exterior

• Sunroof Seal Failure: The sunroof seal can wear or become damaged, allowing water to leak into the interior. Solution: Replace the sunroof seal. Estimated Cost: $200 - $400

Interior

• Dashboard Pixelation: The LCD display on the dashboard can develop pixelation or fading. Solution: Replace the LCD display. Estimated Cost: $500 - $1,000
• Climate Control Malfunction: The climate control system may fail to regulate temperature or airflow properly. Solution: Inspect and replace faulty components in the system. Estimated Cost: $300 - $1,000+

Summary:

The 1990 BMW 735iL is a well-built luxury sedan, but like any vehicle, it has its share of common issues. The engine and transmission are generally reliable, but potential issues with the head gasket, timing belt tensioner, and transmission leaks should be considered. Suspension components may require occasional replacement due to wear and tear. Electrical problems can range from minor battery issues to more complex wiring harness repairs. Overall, the severity and cost of the issues are manageable, and the 735iL remains a desirable classic for enthusiasts who appreciate its performance, comfort, and timeless design.