Q: Could an oil leak turn into a transmission problem?

asked by on December 23, 2016

I had the misfire symptoms, shaking (both which would go away 30 mins to 1 hr into it running on a cold morning) and check engine light on (that would turn on and off). Replaced the valve cover gaskets, spark plugs and boots as it was very bad but after doing that it now randomly shakes at idle, check engine light still on and now when slowing down my gears slam at 20 MPH and jolts the car as if I had slammed the brakes for a second. You could never hear the car shaking before changing out the gasket and now it is loud and smokey but hoping the smoke is just from the oil that went down the spark plug holes as the oil was pooled up in the wells. It was not smoking at all prior. You can also hear it in the exhaust. No longer has that loss of power sputter with the shaking. What could have happened? Oh and the plugs are the AC Delco double platinum... Could something else be damaged under my spark plugs and oil somehow got into my transmisson?

My car has 122667 miles.
My car has an automatic transmission.

Car idle is rough Inspection $94.99 - $114.99 Get a Quote
Engine is misfiring Inspection $94.99 - $114.99 Get a Quote

Hi there. What seemed to happen is that the spark plug well was full of engine oil and when you removed the spark plugs, the oil got into the cylinders. Now, if the rings were sealing very well, the oil will stay trapped in the cylinder for a little while. This is what seems to have happened. The engine was vibrating as the oil was burning and preventing the fuel from burning properly. This could have caused a loss of power and coated the cylinders with carbon. I recommend putting a can of sea foam in your fuel tank to help clean up the carbon and oil deposits in the cylinders. For the check engine light being on, it is best to use a code reader and scan the computer for any pending or stored codes. This will give you a starting point for a diagnostic troubleshooting location. If you need further assistance with your engine running rough after changing out the valve cover gaskets, then seek out a professional, such as one from Your Mechanic, to help you.

Hello. Since the check engine light is on I would start by scanning the computer for codes. Those codes would help me to determine what the issue is. If you have a misfire that comes and goes it can be caused by a few things. I would start by checking to see if there is still oil getting into the spark plug holes as that will cause the smoke and the misfire. It may just be a coil that is failing. Once the codes are ready the I could identify which cylinder it is then I could diagnose the issue. You should have a certified mechanic, like one from YourMechanic, check this out to [diagnose why the misfire is occurring] https://www.yourmechanic.com/services/engine-is-misfiring-inspection

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


Experienced Mechanic?

Earn up to $70/hr

What others are asking

Check Engine light P0304.
The code P0304 points to a misfire on cylinder number 4. Ford also has a funny cylinder identification pattern, different from many makes, and a diagram should be consulted to determine which cylinder is the right one. The spark plugs...
Car locked in reverse
Hi there. You can be experiencing 1 of 2 things. Your vehicle's brake switch which indicates that the brake is pressed allows you to shift gears may be malfunctioning. These typically deteriorate overtime causing the shifter to be "stuck." Secondly...
Car shuts off while idling
Hello. This can be caused by many things on this vehicle, but the most common one is the crankshaft position sensor (https://www.yourmechanic.com/services/crankshaft-position-sensor-replacement). I have seen many of these fail on this car and cause this. I usually use a scan...
Crank bit won't turn over
This suggests you may have a fuel supply issue if you have confirmed that you do have spark. Try pulling one of the spark plugs out after cranking it to see if it is wet with fuel. If it is...
Doesn't $800 seem a little high for an oil pan gasket replacement?
Hello. This is less than an issue about the ethics of a dealership service center, and more about the cost overhead of the 2 different business models (dealership and YourMechanic). A dealership has a much more expensive cost structure: building,...
car does not accelerating smoothly until it reaches 30 mph.
Hi there: The throttle position sensor (https://www.yourmechanic.com/services/throttle-accelerator-pedal-position-sensor-replacement) is typically mounted to the gas pedal, and essentially translates the movement of the pedal (speed and position) into voltage, which tells the car’s computer how much fuel to supply for engine acceleration....
Service AdvaceTrac Warning Light is on in my car
Your car is equipped with wheel speed sensors (https://www.yourmechanic.com/services/abs-speed-sensor-replacement) at each of the four wheels which monitor wheel speed while relaying this information constantly to the ABS and traction control system which are controlled by the car's ECU. When the...
Thank you
Check the wiring to the fuel pump and make sure that it is plugged in properly. The fuel pump will stop working if the wiring disconnects from the pump. If the wiring is connected properly, then the fuel pump relay...

Related articles

What Is the Shelf Life of Motor Oil?
If you plan on storing your oil, it's good to know how long motor oil lasts. Store your motor oil in a cool, dark place to make your oil last longer.
How to Buy Good Quality Spark Plugs
Sparks Sparks make everything happen! Without spark plugs, your vehicle would never be able to kick off combustion, providing the necessary power to make your car go forward. If your engine is starting to misbehave, by either stalling, lurching, or...
When Should I Change My Oil?
Changing oil in your car needs to happen at specific intervals. Oil change intervals vary, but it's best to change oil every 3,000 to 7,000 miles.