Q: The oil pressure is fine but when I crank the car and when it warms up it drops down to maybe 20 and starts knocking a little. Whats wrong?

asked by on

Is it oil pump or pressure sensor

My car has 161407 miles.
My car has an automatic transmission.

The first step is to check the level of the oil. Assuming it’s full, and there are no leaks on the system, it could be the pump or the sensor. The easiest way, despite that you need a special tool, is to hook up a gauge inline and test the oil pressure. This will allow you to see if you truly have a pressure issue or if the electronics are to blame. This gauge will replace the oil pressure sensor/switch. Remove the switch, thread in the sensor (carefully, and snugly), and start the vehicle. If the pressure is below the ratings for your vehicle, and the oil level is full, you will want to replace the pump. You will also want to make sure the passages are clean and sludge free. Bent, damaged, or clogged oil lines can also cause pressure issues. If the pressure is where it needs to be, the issue is the sensor and it should be replaced.

Was this answer helpful?
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details
  1. Home
  2. Questions
  3. The oil pressure is fine but when I crank the car and when it warms up it drops down to maybe 20 and starts knocking a little. Whats wrong?

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: The car cannot start, oil pan dented, lost oil pressure

Hello there, there are a few problems that could result in the loss of oil pressure and not being able to start. If the pan was hit in the right place it may have interfered with the oil pickup. The...

Q: Battery seems to be dead

You need to see if you can jump start using jumper cables. If you can then remove and clean inside the of the cable ends. If you still cannot get your battery to get a good connection and vehicle can...

Q: Brakes not working correctly.

Do not drive your car in this condition, have a mobile mechanic come inspect your car to inspect the damage. The hydraulic master cylinder is the heart of your brake system, it provides flow to the brake calipers and rear...

Related articles

How Long Does a Heater Control Valve Last?
Keeping the right amount of coolant in a car is essential in keeping the engine at the right temperature. Failing to have the right amount of coolant or even bad elements...
P0052 OBD-II Trouble Code: HO2S Heater Control Circuit High (Bank 2 Sensor 1)
P0052 code definition HO2S Heater Control Circuit High (Bank 2 Sensor 1) What the...
How to Avoid Back Pain in a Car
If you have back problems, sitting in a car for an extended period of time can be excruciating. Even without back problems, you could experience discomfort and soreness from...