Skip the auto shop - Our mechanics make house calls

Q: My car is making a knocking noise - 1986 Oldsmobile Delta 88

asked by on

I have a slight knock when the car is in the idle position but once you give it gas it goes away what is the problem!

The first concern is your oil system. Do you have full and clean oil in the vehicle? If the fluid is low, or there is an oil leak, the vehicle will have low oil pressure at idle. When the engine is running at a faster RPM, the oil pump is working harder and supplying a greater flow of oil to the engine. This may be one reason you are hearing a knock.

You may also be hearing different types of combustion going on in the cylinders. If the engine is not running at its prime, during idle the combustion cycles can become unstable. This may sound like a "knock" under some conditions. A tune up is one of the best ways to access a situation like that.

I recommend having a certified mechanic, such as one from YourMechanic, come to your location to determine why the engine is knocking and suggest any necessary repairs.

Was this answer helpful?

Need advice from certified mechanic? Get help now!

Over 1000 mechanics are ready to answer your question.
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Fair and transparent pricing

Get a quote

What others are asking

Q: Knocking/Rattling sound in the engine bay on startup.

It would be difficult to tell what is causing the noise without first inspecting the vehicle using a mechanic's stethoscope on various locations to determine exactly where the source of the sound is. However, it is possible that the noise...

Q: Engine bogging down when making a turn

For your 2002 Oldsmobile Bravada, you may have a problem in the transfer case causing the AWD to be engaged when it shouldn't. In this case, the transfer case encoder is not working correctly and should be replaced. The problem...

Q: Fiero begins to overheat when at idle/ driving slow

This can be caused by a number of things such as low coolant levels, a faulty thermostat, or a failing coolant fan switch. As you may know the coolant fan switch helps to maintain the proper coolant temperature by turning...

Related articles

How Do Power Car Windows Increase Passenger Safety?
Power windows are responsible for approximately 2,000 emergency room visits every year. When a power window closes, it exerts enough force to bruise or break bones, crush fingers, or restrict an airway. Though...
P0240 OBD-II Trouble Code: Turbocharger Boost Sensor B Circuit Range/Performance
P0240 code definition Turbocharger Boost Sensor B Circuit Range/Performance What the P0240 code means P0240 is an OBD-II generic code triggered when the Engine Control Module (ECM) detects the intake boost...
P2103 OBD-II Trouble Code: Throttle Actuator Control Motor Circuit High
P2103 means there is a fault with the throttle actuator control motor circuit, likely due to a defective electrical component or part.