The culprit is oil collecting in the cylinder and not being burnt off. Generally it is caused by 1) leaky valve seals, 2) worn rings, 3) leaking head gasket.
The first check should be a compression test to verify if the rings or heads are leaking. If they are fine the only thing left is the valve seals. Not an easy fix but can be done by a home mechanic with some effort.
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Related Questions
What is a fouled spark plug?
Fouling spark plugs can happen when the tip temperature is insufficient to burn off carbon, fuel, oil or other deposits and causes spark to leach to metal shell...no spark across plug gap will cause a misfire. Wet-fouled spark plugs must be changed as they won't fire. Dry-fouled spark plugs can sometimes be successfully cleaned by bringing the engine up to the operating temp.
Why do spark plugs fail?
Wear. Fouled. Cracked.
What causes a 2001 Neon to jerk when you speed up?
Faulty/fouled spark plugs or spark plug wires. I had this problem and a set of new wires fix it.
Why are the spark plugs black on my 1993 Toyota tercel?
if the spark plugs are black because your car is running too rich. your plugs are fouled.
Why does my car putter when running?
possible fouled spark plugs, bad fuel. check both and if both are good, get back to me.
What happens when the spark plugs of a 2001 Pontiac Grand Prix are fouled out?
intake manifold gasket is leaking and water is getting on the plugs, plastic piece melts and causes leak
Can fouled spark plugs cause engine shaking and knocking as well as loss of power?
Yes, fouled spark plugs can cause engine shaking, and loss or power. I'm not sure about knocking but I'd guess that too.
Could the spark plugs be the reason why your car wont start?
Absolutely. Worn plugs or carbon-fouled plugs can cause an engine to not start.
What causes knocking after changing the spark plugs?
Possible wrong heat range of plug. Make sure you have the right plugs for the vehicle.
Will fouled spark plugs couse a Chevy 350 not to crank after cleaning the carb?
no The starter should engage whether the plugs are fouled or not. However, the engine may not start if enough plugs are fouled. If you feel that you have flooded the engine or fouled the plugs you may need to clean them before it will start. If you have caused the carburetor float level or other settings to be significantly changed, the engine will flood and it will not start.
When should you change the spark plugs on your motorcycle?
You should check your spark plugs periodically as they can give an indication as to how your engine is running. If the spark plug is fouled the engine wont work as efficiently as it's supposed to. A normally operating engine should result in a light brown discoloration, check your spark plugs against a reading chart like http://www.ngksparkplugs.com/techinfo/spark_plugs/faq/faqread2.asp If the spark plug is fouled or eroded, replace it. It's a simple job and spark plugs aren't too expensive.
Do spark plugs loose power?
Spark plugs do not loose power, rather, they become worn and erroded. On occasion they may also become fouled, indicating a mechanical or fuel problem.
Why on 1990 Subaru legacy when you get on the gas it hesitates what would be wrong?
If you have good power when on highway and it only hesitates at low speed or from a stop you have a weak spark somewhere. Possible causes: Needs a tune up Fouled spark plugs Old plug wires Ignition coil about to die improper timing
Will spark plug cause gone bad cause car not to start?
If the spark plug or plugs are bad the car will not start If the car does not start, (for various reasons) the spark plugs may be fouled or damaged by this and require replacement.
How do you know if the spark plugs are bad?
Spark plugs are cheap so, when you pull them to read them, don't put them back in. Replace them with new. To read the plugs, you need to compare them to the pictures at the link. They will tell you about your engine's health. Fouled plugs are not the problem, they are the symptom.
What causes spark plugs to stop firing?
No spark from coil, bad plug wires, or bad plugs.
How can you tell if your car engine is burning oil?
spark plugs fouled with oil. blue smoke from tail pipe.
How can you tell if a spark plugs are fouled out on a dodge 1500 5.9?
You have to remove them and inspect.You have to remove them and inspect.
Why would the check engine light come on after changing the spark plugs on a 2003 gmc envoy?
Have the codes checked to know possible causes.Have the codes checked to know possible causes.
Why does an engine run roughly?
if it's runninng rough my guess could be spark plugs are fouled up. if not then next check the spark plug wires then the distributor.
Can worn spark plugs cause a p0420 code?
If the spark plug is fouled ("too rich" or in other words: Too much fuel, not enough air or spark to ignite): It is possible that the rich fuel will dirty up an O2 sensor, which may trigger a P0420 error.
Would a tune up take care of a fouled spark plug issue?
only if the plugs and wires that replaced them where not fouled most time yes is the answer. after changed start the vehicle and it should be aparent.
What causes sooty exhaust and poor fuel economy in a 1989 Plymouth Reliant K car?
There are many possible causes. Including, worn spark plugs, failed oxygen sensor, leaking injector, improper reading from the MAP or TPS sensors, etc.There are many possible causes. Including, worn spark plugs, failed oxygen sensor, leaking injector, improper reading from the MAP or TPS sensors, etc.
Why would there be back firing in a 1996 Oldsmobile Ciera after the fuel pump has been replaced?
Could be as simple as fouled spark plugs.
What is replacement spark plugs and what is the gap?
Sparks plugs deteriorate or become fouled over time. Replacement spark plugs are spark plugs you buy to replace the old ones. What the gap is supposed to be set at.. that varies by vehicle. If you're trying to do this, and you don't know how, I'd very strongly suggest you buy a Chilton or Haynes service manual for your vehicle.
