Q: Engine Knock only during start up and acceluration, some oil found in spark plug well also. possible rod knock

asked by on

2007 Scion Tc Auto, I have a somewhat noticeble knock only during startup( less than 3 seconds during turning over) and during acceluration between 2k-3krpm. During idle it sounds completely normal no abnormal tapping only slight value tapping which is said to be normal in these cars. I notice some oil on my spark plug and in the well of cylinder 1 during tune up other three are dry. Also smokes a bit near the headers near the first value. Could this be sign of possible rod bearing failure, or spark knock? no CEL or oil level lights are on.

My car has 167000 miles.
My car has an automatic transmission.

Hi there:

If you’ve found oil in the spark plug well is a sign of a fairly serious problem that should be inspected and repaired immediately. It is almost always due to a failing gasket or O-ring but can also be the result of a failing piston or worn valve guides. This could be the source of the engine knock and other issues you’re having. It’s probably a good idea to have a professional mechanic complete a oil is leaking into spark plug well inspection, so they can determine what’s causing your issues.

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. Engine Knock only during start up and acceluration, some oil found in spark plug well also. possible rod knock

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: What's the best way to check for Evap small leak. I'm getting code P0442

P0442 indicates that you have a small leak in the evaporative emission system. Many times this is caused by a loose or faulty fuel cap. Make sure that the cap is tight and in good condition, so that it seals...

Q: How difficult is it to replace the radiator in a 07 X-Type Jag?

In order to verify the leak you will need to have the cooling system pressure tested to see if it is just a hose or the radiator is leaking. This way you do not replace good parts. You may have...

Q: My 2005 Scion tC won't start?

Hi Courtney. Thanks for writing in tonight about your Scion. Although a battery might be charged, it is possible that it has worn out and does not have enough cranking amps to activate the starter and power ignition system components...

Related articles

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...
What are the Car Pool Rules in Hawaii?
Hawaii is widely regarded as a land of vacation and relaxation, and as such, its scenic roads and routes are far better known than the state’s freeways. But, as with all...
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.