1990 Pontiac LeMans Is Leaking Oil

Discovering the Causes of Oil Leaks in Your 1990 Pontiac LeMans and How to Fix Them Effectively

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Reviewed by
Devin Cabugcal
Written by RepairPal Car Genius
Updated January 14, 2025
0%
80% chance it's the
Oil System Components
0%
20% chance it's the
Engine Gaskets
The most common reasons a 1990 Pontiac LeMans is leaking oil are oil system component failure and leaking engine gaskets.
  • Oil System Components: A worn or damaged oil pump or filter can lead to low oil pressure, resulting in inadequate lubrication and potential engine damage.
  • Engine Gaskets: A worn or damaged engine gasket can lead to oil or coolant leaks, resulting in engine overheating or loss of lubrication.
Proper diagnosis will determine the exact cause of your symptom, saving you money on unnecessary repairs. The diagnostic experts at RepairPal Certified shops have the right tools and experience to solve any symptom.

How much does it cost to fix a 1990 Pontiac LeMans is leaking oil?

Common Repairs

The total repair cost will vary based on the condition of your vehicle and the number of repairs needed to fix your symptom. Proper diagnosis will save you money by finding the exact repairs needed to fix your car right the first time.

Oil pans don't wear out or break like other parts, they generally only need to be replaced because of external damage from an accident or an improperly tightened drain plug. The main symptom you will experience is an oil leak underneath the engine of your car. The oil that leaks from a damaged oil pan will range from dark brown to dark black. If the leak is large enough or occurs for long enough the oil level will be low enough to turn the oil pressure or low oil level warning light on.

An oil leak may be noted on the ground where the vehicle is parked. However, many vehicles have plastic trays underneath the engine that may catch leaking oil and conceal the leak. In such cases, a low oil level, a burning oil smell, or even smoke from oil burning in the engine bay may be noted.

»MORE: Signs of a bad oil pan gasket

The engine oil pressure warning light will come on if the engine oil pressure is low, or if the oil pressure sensor is faulty. In either case, engine power may be reduced significantly. The check engine light may also illuminate, and an on-board diagnostic (OBD) trouble code will be stored in the vehicle's computer.

What are the initial diagnostic steps to take for an oil leak in a 1990 Pontiac LeMans?

When faced with an oil leak in your 1990 Pontiac LeMans, the first step is to locate the leak by checking underneath the vehicle for any visible oil spots or puddles. Once you have a general idea of where the leak might be coming from, inspect the oil pan for signs of damage or corrosion, as this is a common culprit. Next, examine the oil filter to ensure it is properly secured and free from leaks, as a loose connection can lead to oil escaping. Don’t forget to check the oil drain plug; it should be tightly fastened to prevent any leaks. Additionally, inspect the valve cover gasket for wear or damage, as this can also be a source of oil leakage. The oil pressure sending unit is another component to consider; look for any signs of leaks here as well. Finally, broaden your inspection to include other potential leak sources such as oil cooler lines and the oil pan gasket. By systematically following these diagnostic steps, you can effectively identify the source of the oil leak and take the necessary actions to resolve the issue.

What are the common causes of oil leaks in a 1990 Pontiac LeMans?

When dealing with oil leaks in a 1990 Pontiac LeMans, it's essential to understand the common culprits that may be at play. One of the primary issues is a worn or damaged oil pan gasket, which can deteriorate over time, leading to significant leaks. Additionally, the valve cover gasket is another frequent source of oil seepage; if it becomes worn or damaged, it can allow oil to escape. Another potential problem is a leaking oil filter, which may occur if the filter is not installed correctly or is compromised. Furthermore, a cracked or damaged oil pan can also contribute to oil leaks, necessitating careful inspection. Lastly, degraded oil seals around critical engine components, such as the crankshaft and camshaft, can lead to leaks as they age. Addressing these issues promptly is crucial to prevent further engine damage and ensure the vehicle operates smoothly. Regular maintenance and inspections can help identify these problems early, allowing for effective DIY repairs.

How urgent is it to address the oil leak in my 1990 Pontiac LeMans?

Addressing an oil leak in your 1990 Pontiac LeMans is not just a matter of routine maintenance; it is an urgent issue that requires immediate attention. Ignoring an oil leak can lead to a significant drop in oil levels, which compromises the lubrication of essential engine components. This lack of lubrication can result in severe engine damage over time, leading to costly repairs that could have been easily avoided. Furthermore, an oil leak can cause the engine to overheat, as insufficient lubrication prevents proper cooling, increasing the risk of catastrophic engine failure. The safety implications are also considerable; leaking oil can drip onto hot engine parts, creating a fire hazard that endangers both the vehicle and its occupants. Additionally, the environmental impact of oil leaks cannot be overlooked, as spilled oil can contaminate soil and water sources, contributing to pollution. Therefore, it is crucial to address any signs of an oil leak in your Pontiac LeMans promptly to safeguard your vehicle's performance, ensure your safety, and protect the environment.

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1990 Pontiac LeMans Oil Leak Causes & Repair Costs