I changed the coil pack spark plugs and plug wires my car still runs bad why

My car runs bad when I changed the plugs plugs wires and coil pack I don't understand why still doin that

My car has 89000 miles.
My car has a manual transmission.

Experienced mechanics share their insights in answering this question :
If the engine is running bad then you should be getting a code set in the computer. If not, then a scanner should be used to view data to see if the engine is running lean or rich. Check the intake tube between the mass air sensor and the intake throttle body for any leaks. Clean the mass air sensor and monitor it to make sure it is reading the correct barometric pressures. These sensors are known to not give the correct barometric pressure for the altitude you are at.

I’d suggest you get the car inspected by a certified mechanic who can diagnose your rough running symptoms and make the necessary repairs to get your car running smoothly again.

How to Identify and Fix Common car Problems ?

Our sources include academic articles, blog posts, and personal essays from experienced mechanics :

Bad spark plug wires can interfere with the electrical current flowing to the engine, making it difficult for the engine to complete the combustion cycle. An incomplete combustion cycle can cause an engine to misfire, which means your car may jerk, stumble, or briefly lose power.
A clogged or failed exhaust gas recirculation or crankcase ventilation valve or faulty oxygen sensor can send the wrong signals to the computer and cause misfires.
Your vehicle`s spark plugs can actually cause the coil death. Dirty, misfiring, or worn spark plugs can damage the ignition coil, so plan to have your spark plugs changed when recommended.
Excessive heat and vibration can cause the insulating material to break down and create internal coil failure. Worn secondary ignition components such as spark plugs or wires can cause a coil work harder, require more voltage, and therefore significantly reduce the operating life of the coil.
Yes. While the damage may seem small initially, the longer you drive with a bad oxygen sensor, the worse the damage will become. Eventually, you may experience rough idling, poor acceleration, engine misfires, an illuminated check engine light, and failed emission tests.
Vibration damage – Constant wear and tear caused by engine vibration can loosen the electrical connection at the spark plug. This causes an increase in the voltage required to fire the spark plug, which could damage the ignition coil as well as the spark plug wires.
The most common causes of misfires are worn, improperly installed, and mishandled spark plugs, malfunctioning ignition coils, carbon tracking, faulty spark plug wires and vacuum leaks.
Even a dirty MAF sensor can cause a lean code and/or misfire to occur. The engine may be stalling because it isn`t getting enough throttle opening.
What kills ignition coils is location; being mounted in one of the hottest, most vibration prone and dirtiest parts of the engine. Modern ignition coils are typically located between two camshafts on the valve cover and exposed to dirt and oil.
Misfiring Engine

This is caused when fuel fails to ignite consistently during the combustion cycle. It could be that the spark plugs are failing, but it could also mean that the charge from the battery isn`t strong enough, and the ignition coil needs replacing.

Causes of lean misfire that only affect one cylinder include a dirty fuel injector, an open or shorted fuel injector, or a problem in the fuel injector driver circuit (wiring or PCM). Compression problems that may cause a misfire include a burned exhaust valve, bent intake or exhaust valve, or leaky head gasket.
Engines that idle in a clunky or rough manner could be suffering from misfiring. In essence, when a misfire occurs and the air to fuel mixture in the cylinder becomes compromised, your engine essentially may jump up and down, causing your car to start and stop suddenly.

Relevant Questions and Answers :

the most relevant questions and answers related to your specific issue

I changed the coil pack spark plugs and plug wires my car still runs bad why
ANSWER : If the engine is running bad then you should be getting a code set in the computer. If not, then a scanner should be used to view data to see if the engine is running lean or rich. Check the intake tube between the mass air sensor and the intake throttle body for any leaks. Clean the mass air sensor and monitor it to make sure it is reading the correct barometric pressures. These sensors are known to not give the correct barometric pressure for the altitude you are at.

I’d suggest you get the car inspected by a certified mechanic who can diagnose your rough running symptoms and make the necessary repairs to get your car running smoothly again.

replaced bad coil pack and new coil not sparking car starts but runs rough engine light on blinks sometimes
ANSWER : Hello and thank you for your questions. If your engine was rebuilt about 10 months ago, the question is to determine if the management system has been installed as well. With the symptoms that you are having, it sounds like the coil packs are old and in need of replace. You replaced numbers 1 and 4 and now number 6 is not firing. I recommend replacing number 6, 2, 3, and 5. This will ensure that you have all 6 coil packs that are new.

Just because the coil packs are okay during a test doesn’t mean that they are functioning correctly. Coil packs on Buick vehicles from 1998 – 2005 last between 150,000 to 200,000 miles. I also recommend having your fuel injection system flushed. Unless you have new injectors, the old injectors could cause a cylinder to fail, even though it is working correctly. These symptoms can cause the engine to have a rough idle and rough running during conditions. If you need assistance troubleshooting the rough running condition, I recommend having a professional, like one from YourMechanic, inspect the car and move forward with repairs.

Engine light fault. There was a bad spark plug and a failed ignition coil. Replaced both the coil pack or spark plug.
ANSWER : Hi there. If the light is coming on then shutting off and returning on, then if the issue is for the same coil, there could be an issue with the wiring on the coil plug. Check the wiring on the coil plug and see if the wires are split, broken, or burned. If there is nothing wrong with the plug, then the main engine harness has an issue / short and may need replaced. If you need further assistance with your ignition system, then seek out a professional, such as one from Your Mechanic, to help you.

Need to replace bad spark plug & coil pack on Ford Expedition but not sure what else I need besides the plug and coil pack?
ANSWER : Hi There,
I would recommend having an expert from YourMechanic come to your location to take a look at the vehicle to first determine what the cause of the misfire is if this has not already been done. Engine misfires can be caused by many different problems and are generally caused by either a spark or fuel issue or in some cases, a combination of both. Spark related problems generally will result from things like ignition coils, crankshaft position sensor, spark plugs, spark plug wires or ignition modules not working properly. When the misfire results from a fuel related issue, this is commonly related to a lean fuel condition (lack of sufficient fuel supply to the motor). Fuel related misfires can be caused by many different things such as low fuel pressure, faulty or dirty fuel injectors, a faulty O2 sensor, a dirty or failing mass air-flow sensor, a faulty or dirty idle air control valve or a vacuum or intake leak. When the fuel supplied to the combustion chamber is insufficient, this results in an ignition (spark) that is igniting a less than balanced load of fuel and air. This results in a misfire or an explosion in the cylinder that is much less powerful than the other cylinders. This creates a loss of power that resonates throughout the motor additionally causing other problems with ignition and fuel timing. Due to the number of different things that may cause an engine misfire, the quickest and easiest way to diagnose this type of problem is to hook the vehicle up to a scanning tool which will download any potential fault codes that may have registered in the vehicle’s computer as a result of the poor running condition. I would recommend having an expert from YourMechanic come to your location to diagnose your misfiring problem.

Spark plug chaos. Rubber stoppers are preventing the spark plugs from coming out.
ANSWER : Hi there. Try using a pair of small needle nose pliers to pull off the rubber boots from the spark plugs. As you pull, twist the rubber boots to break them free. If you cannot get the rubber boots off, then try using some mineral oil on the boots to aid them off, then clean off the oil with soap and water with degreaser. If you need further assistance with removing the boots from the spark plugs, then seek out a professional, such as one from Your Mechanic, to help you.

Engine will not stay started. I have replaced idle control valve map sensor spark plugs spark plug wires no check engine light is
ANSWER : You have a problem with the distributor assembly. I recommend replacing the distributor assembly. This will replace all the possible sensors and coil for the ignition and fix the problem you have.

I recently changed out a bad coil pack that had been bad for a month. Literally today it got changed and shuts down while driving
ANSWER : Hello. The bad coil wouldn’t have caused the crank sensor to fail. Crankshaft sensors are the most common failure on this engine so it should just be a coincidence. I would use a scan tool just to make sure that there is no rpm reading before replacing it though, as there are some other problems that can occur, but are not as likely. If you need help with this, consider having a technician from YourMechanic come to your home or office to diagnose this problem with a scan tool and replace the crankshaft sensor if necessary.

Spark plugs,spark wires,icm,ecm,ignition coils,replaced engine,crankshaft sensor,harmonic balancer car still misfires, wont start
ANSWER : Hi there. If your car had overheating issues before this misfiring issue began, it is quite possible that you have some internal engine damage like a blown head gasket that is the primary source of your troubles. Other damage to cam sensors and ignition timing and fuel components can also cause these issues. Before you sink another dollar in attempting repairs, I would strongly recommend having a professional mobile mechanic from our team come to your location and complete a car is hard to start inspection so they can pinpoint the root source and recommend the best course of action.