Note to Reader 2: Like the rest of my recent posts, this multi-section post will give you some of the most common symptoms of engine problems. A list of causes and probable solutions will be posted with each section. Having said that, read on to find out more about the common engine problems and how you can address these issues.
If your car starts out fine but starts jerking and bucking, particularly when you’re running at a low speed…
Possible Cause: Broken O2 sensor. If you have a broken O2 sensor, then naturally this component is going to throw your air-fuel mixture out of the loop. Your engine is going to be fed with air/fuel mixture that’s either too rich or too lean, causing your engine to run roughly.
Possible Solution: Find your oxygen sensor and replace it if necessary. This component is usually mounted inside your exhaust pipes. It’s pretty small, around the size of a clothespin, so keep your eyes open for this component. (By the way, the oxygen sensor is a small device that’s used to measure the amount of oxygen in your exhaust emissions. The moment there is too much or too little oxygen in your air-fuel mix, the oxygen sensor sends signs to your engine computer to lessen or increase the flow of fuel—whichever applies.)
Possible Cause: Your car has vacuum leakage. To check this, you’ll need to have a stethoscope—the kind sold for less than $15, preferably (mainly because you won’t be using it often). Put the stethoscope against the hose and listen for signs of air leakage. This usually comes in the form of a high, shrill, squealing sound. Also listen between your car’s intake manifold and carburetor or throttle body. In most cases, the leak should come from your car’s rubber, vacuum hose. Inspect the hose for signs of cracking or pinching.
Possible Solution: Repair and/or replace damaged components as soon as possible.
Possible Cause: Your EGR valve is malfunctioning.
Possible Solution: Repair or replace this valve if needed, to restore your ride’s power easily.
Note to Reader 3: If stalling is the biggest engine problem you have, I also suggest looking into your fuel system. It’s possible that your fuel pump is no longer creating enough pressure to transfer gas from your fuel tank to your engine. Use a fuel pressure gauge to be sure. Also, do check your fuel filter. Remember, you have to replace your filter regularly to avoid grime buildup that hinders fuel flow!
If your car runs well during low speeds but starts surging or jerking every time you depress on your gas pedal…
Possible Cause: Ignition trouble—usually worn spark plugs. Check your spark plugs for signs of damage.
Possible Solution: If you notice that your plugs are starting to look rather worn-down around the electrode corners, replace them.
Possible Cause: Arcing spark plug wires. Arcing is a type of electrical phenomenon where electricity or electric current builds up and jumps the gap on your circuits. This is particularly dangerous since the extreme heat caused by the electric charge can ignite or damage any type of combustible material nearby.
Possible Solution: Check your spark plug wires for signs of arcing. It’s best to conduct this inspection at night. Remember, even the tiniest signs of light in your spark plug wires can yield monstrous auto problems when left unaddressed. So if you’ve got arcing on your wires, replace your spark plug wires as soon as possible.
Possible Cause: Poor auto maintenance. Yep, you read that right. Remember my previous post where I discussed the importance of auto tune-ups? A malfunctioning or erratically performing engine is a sign of poor maintenance.
Possible Solution: Get a tune-up. Or better yet, do it yourself. During your tune-up, don’t forget to replace your worn or damaged distributor rotor and cap.
Possible Cause: Damaged catalytic converter. The catalytic converter is the component in your car that converts harmful gases like hydrocarbons, carbon monoxide and oxides of nitrogen into less harmful byproducts like water vapor and carbon dioxide. The moment it stops operating properly, toxic gases build up inside your engine system, leading to damage.
Possible Solution: Replace your catalytic converter.
Possible Cause: Transmission troubles. Okay, so are you sure that the problem lies in your engine and not your transmission? Keep in mind that once your transmission slips, your car’s naturally going to be a lot harder to control. Check out my previous post on steering and transmission problems to determine which parts you need to repair or replace.
Possible Solution: Repair or replace damaged transmission components.
Possible Cause: Leaks coming from your exhaust. Exhaust leakage tends to confuse your oxygen sensor, causing this measuring probe to send out the wrong information to your engine computer. The result is uneven fuel-air mixture that’s naturally going to cause poor engine performance.
Possible Solution: Check out your exhaust system for signs of leakage. If there is any, do repair or replace the damaged component.
Note to Reader 4: If all else fails, once again, go back to your automatic transmission. It’s possible that you have a lock up converter that’s staying locked up, making it difficult to control your car’s movement—if there’s any. Simply remove or disable your lock up converter to get your car working properly. Have your local mechanic check your transmission for other signs of damage, if these auto symptoms continue.