Spark plugs are usually one of the first things to go wrong on an older car. And if they’re not replaced with better quality plugs, your old car may not even start anymore.
It’s really important to know what causes a bad spark plug, and how you can remedy it if you’ve got transmission problems at idle or when you first start your car up. Here’s what causes a bad spark plug and how to fix it!
Can bad spark plugs cause transmission Problems?
No, bad spark plugs do not directly cause transmission issues. However, if the spark plugs are not too good they may misfire and deliver lower torque to the transmission. This prevents the transmission from shifting gears which can cause your car to run rough with less power.
Spark plugs and transmission are not connected at all! The spark plugs are connected to the engine, while the transmission is connected to the wheels. If your vehicle has transmission problems it’s probably not bad spark plugs! If you’re having issues with your vehicle it’s a good idea to check out what’s causing them.
If you’re experiencing transmission problems it’s most likely either a faulty wiring harness or something else entirely. If you’ve got bad spark plugs in your car, we strongly recommend that you replace the sparkplugs with ones that are of higher quality. While the new-for-old rule of thumb is that iridium spark plugs last twice as long as standard, the current price difference is probably too great for most people to afford.
What Causes Bad Spark Plugs?
While most people think that only high-quality spark plugs will get their vehicles running smoothly, the truth is more complicated than that. Spark plugs fall into two categories: iridium and platinum-iridium (PtIr).
Iridium spark plugs are the more common of the two, and cost a lot less than platinum plugs. Platinum-iridium are slightly better, but platinum actually erodes much faster than iridium, which means that while they last longer The real problem with spark plugs is that most people don’t actually know what causes a bad spark plug.
The biggest reason for a bad spark plug is carbon fouling. When you take away the insulation on your wire harness inside your car’s engine, you expose the wires to all kinds of crap – dirt, oil grime, and other contaminants. They’re even exposed to engine heat where they get worn and dirty.
When the spark plugs are next to the wires, they have to work hard in order for the engine to keep running. I know this might sound obvious, but you can actually see your plugs get black from carbon fouling.
Another common cause of bad spark plugs is caused by overheating, if spark plugs start to overheat they cause the electrodes to get damaged faster. This causes the plug gap to become misaligned and prevents electricity from flowing smoothly. In a nutshell, installing low-quality spark plugs in your car can cause damage to your engine.
Can a Spark plug misfire cause transmission problems?
No, a misfire will not directly cause transmission problems. however, indirectly since a misfiring engine makes the car lose power, the transmission will have difficulties getting enough torque from the engine this will make it harder for transmission to shift up and down but does not damage it.
What causes your transmission to jerk?
One of the biggest things that causes an automatic car to jerk is the transmission fluid is low or needs replacing. The transmission fluid needs to flow smoothly through the system to ensure that the torque is transferred from your engine to the wheels. A problem with your transmission fluid will often cause a “jerking” feeling when you’re trying to take off or a bucking feeling when you’re at higher speeds.
On Manual transmission, the common cause for jerking is damaged clutches, worn gear synchros, or sometimes damaged main shaft. If you’re experiencing transmission problems with your car, we strongly recommend that you take it in for professional inspection of the transmission.
If the transmission is worn out, a professional will be able to replace it for you at a very low value. It’s also possible that fluid replacement may be necessary if it’s low.
How do you diagnose a bad transmission?
The symptoms of a bad transmission are often the same as with any other form of mechanical breakdown. If your car is jerking when you’re driving (often through a parking lot), or it’s spitting and clicking out of gear, then it’s probably transmission problems.
Sometimes transmission issues can be difficult to identify, and it may be necessary to take your car to a professional mechanic. A proper inspection will tell you whether the transmission is bad or not. It’s also possible that there are other issues with your engine that are causing it to misfire and jerk, so a professional will be able to take a look at your vehicle and diagnose where the problem is coming from.
How to Avoid Spark Plug Issues
In order to avoid getting into this mess, it is advised to change spark plugs at approximately 40,000 miles (65,000 km) or as instructed in the owner’s manual.
You can notice a worn-out spark plug by observing the distance between the center and side electrode, the distance is supposed to be 40 thousandths of an inch and if it is any greater than that, then you should change them.
You can also diagnose an engine misfire by plugging in an OBD scanner and looking for engine misfire codes, however, most codes are only given by the ECU when a certain parameter is met and, in several instances,, misfiring starts happening before the ECU trips any code.
When changing spark plugs it is always good to stick with OEM (original equipment manufacturer) plugs as they are made to provide optimum performance, generally car manufacturer purchase them from other companies,
and therefore it is better to buy them for a local store, doing so will save you a considerable amount of money. Try to change spark plugs when your car is cold and tighten them only at the torque level mentioned in the owner’s manual.
You may not encounter any kind of engine misfire if you do all your car’s periodic maintenance in time, therefore it is always a great idea to take proper care of a car as it helps in avoiding a variety of problems.
Robert Anderson is a world class motorhead who rebuilt his first carb at age 10, his first engine at age 15, and completed his first full hotrod build when he was just 18! Previously, he has ran a part warehouse, delivered pizzas, and managed the service department for a $20 million/year revenue dealership. Robert knows cars like few others and he is passionate about sharing his knowledge.
