Why Won’t My Spark Plug Screw In? Easy & Quick Fixes

Spark plugs belong to one of the most vital parts of a car, so setting them up keeps of great importance to prevent you from ruining its function as well as your vehicle.

Therefore, a lot of guys are hunting up an answer for why won’t my spark plug screw in on an array of car forums these days.

That also explains our presence today to unveil the reason your spark plug won’t go in all the way and help you address some failures associated with this root.

Follow us now to get the details.

Why Won’t My Spark Plug Screw In 

why won't my spark plug screw in
Spark Plug Won’t Screw In

One of the most common reasons for this situation stems from improper installations. In addition, your spark has issues because of wrong specifications or unclean threads.

Spark plugs are part and parcel of the combustion engine, so setting it up plays a key role that doesn’t allow the element to screw up.

Even high-quality spark plugs from NGK or Bosch will face trouble if you don’t assemble them correctly.

There are a couple of roots why your spark plug won’t fit nicely or screw in inside the motor completely. 

Many experts share that improper installation of this part is one of the most prevalent culprits resulting in the earlier issue.

It would be better if you had a look at whether the component has the right specification and whether its threads are clean or not.

How To Remove A Spark Plug That Doesn’t Screw In

damaged spark plug hole
What Is The Ways Remove A Spark Plug That Doesn’t Screw In

As shared earlier, the installation of a spark plug is not simple. And eliminating a plug not screwing in is also a daunting task. You have to ensure that you will detach it properly.

Otherwise, your automobile will manifest some issues (especially when setting the new spark plug afterward) in the coming day, which is somewhat unavoidable.

Thus, we will give you four basic steps in removing any improperly installed spark plug in your vehicle.

Step 1: Locate Your Old Spark Plug

In the first step, you need to determine where your car’s spark plug is, often located in the engine’s cylindrical hole.

Then, you must find the wire linked with it, and on one of the wires’ ends, tug on its boot.

To prevent the wire from being broken physically, don’t pull the wire too much. In addition, when detaching the wires and spark plugs, utilize the proper tools.

Step 2: Utilize A Torque Wrench

After removing the curl or wire, you will need a torque wrench to detach the spark plug hole.

Use the tool on your spark plug, then turn this attachment anticlockwise. This attachment should be unscrewed without any trouble.

Supposing you are struggling in eliminating a spark plug that is too tight, cease a bit before you let it go. To help this process more smoothly, you might consider using some penetrating oil aiming to relax it.

Step 3: Inspect the Existing Spark Plug

Have a look at your old spark plug, and it is not hard to find that its end should be dirty. In case these ends have different colors (assume white or slick), it means the attachment has various issues.

If you are not a specialist in the sector, asking for help from an experienced mechanic is essential. Otherwise, you can push the subject to be worse.

We should normally leave the faulty element out of your car if this is the case.

Step 4: Check The Spark Plug Threads

You should inspect every detail of the engine’s threads.

In case they are filthy, use threading-washing equipment or a specific solution from a technician to clean them properly.

How To Rethread Spark Plug Hole

cross threading spark plugs
How To Fix Of Bad Spark Plug

There are six basic step guides to carry out the process properly.

Step 1

Use a plug “thread chaser” tap, which is the right size with the old poor plug threads, then attempt to clean them thoughtfully.

If the impairment is not great, you probably have a bit of luck and don’t need to order other extra options.

Step 2

If your threads are too extensive, buy a set of threaded inserts and set the kit into the spark plug hole to fix with the plug chaser tool.

A standard threaded insert set consists of a threaded insert, an oversized-threaded tap, and an installation mandrel.

Step 3

To thread the shaving into the cylinder head, apply the bearing grease on the oversized-threaded tap.

Step 4

Thread this tap into the rest of the old threads, slitting oversize new threads when you give the tap a firmer twist.

As you thread and get the same depth as the oil threads on the spark plug, you draw this tap out.

Step 5

Set the insert on the setting mandrel. To screw the insert into the new oversize threads, utilize the mandrel.

Step 6

Install your threaded insert onto the spark plug and next tighten them appropriately.

FAQs About Spark Plug Holes

How Important Are Properly Torqued Spark Plugs?

The location of the spark plug is just right at the engine’s end. The motor cooling, heating, combustion, and compression cycles might all trigger the spark plugs to come loose if not done up tight enough.

When a spark plug is improperly tightened, the cylinder compression will be lost, and then this part inhales O2 via the loose spark plug on its downside.

The amount of excess O2 inside this cylinder leads to the lack of appropriate compression and then ends up with less power and misfires on the engine.

These issues might result in various other failures, such as valve damage, lean codes, motor light on, pre-ignition, cylinder piston damage, faulty cylinder head threads, and so on.

If your plug could be screwed up to specification yet still worked loose, let’s consider that there is some impairment in heat range, cylinder head thread, and improper plug length.

In another case, an overtightened plug can also cause certain difficult-to-fix the cylinder head impairment and might make a botch–up of the plug.

Too much torque might trigger stretching easily, which can separate the threads.

Can A Car Be Driven With A Damaged Spark Plug Hole?

No, there is no chance of driving your vehicle when you find a damaged spark plug hole on your motor.

Some unexpected events may come with a certainly blown spark plug which might trigger engine damage and then lead to a vehicular accident.

Therefore, it is too dangerous to drive an automobile with a faulty spark plug hole on it.

Keep in mind that every step on your plugs has, for better or worse, an impact on your whole car, so you can’t turn a blind eye to the problem of this part.

What Are Potential Issues A Spark Plug Can Face?

Most spark plug issues stem from one key factor, wear and tear. In addition, the way you use your car is an important factor that impacts how long the spark plugs might get damaged.

Hence, one of the common potential problem on the element is rusty, which is a root that triggers a lot of complicated problems for your vehicle’s engine.

Other issues you can encounter include an oil-fouled spark plug or a plug with an improper gap. So it’s best to check and clean the part frequently.

For more detail to clean it check video below:

In The Nutshell 

We bet that you and those who are looking for why won’t my spark plug screw in have reached the answer for this hot topic when you all still stay until these bottom lines.

We would like to emphasize one more time the great importance of a spark plug on a car, so you should put more consideration on its installation as well as its removal to set up a new one.

Thank you for reading, and feel free to let us know if you are stuck in any issues with the rethread spark plug holes. See you soon in our future posts.

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