The 4 Most Common Dodge 318 Engine Problems

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With 318 cubic inches of displacement, 230 horsepower and a torque of 295 lb-ft, the 318 Magnum engine is fired up to hold out against any road challenge. Guess what? Its reliability and reputation are in no doubt as it edges past many of its competitors out there.

Yet, there are a few design-related issues you must be on the lookout for when buying this engine. Over the years, users’ reviews have identified the following common Dodge 318 engine problems:

  1. Weak Transmission
  2. Broken Exhaust Manifold Bolts
  3. Camshaft Sensor Failure
  4. Plenum Gasket Issue

Launched more than three decades ago as the 5.2 Magnum, the Dodge 318 engine has experienced modifications over the years.

You may notice some mechanical, electrical, or hydraulic issues in the second and third generations of this engine; they’re not things to get too anxious about as they are common to all engines.

What Are The Most Common Dodge 318 5.2 Liter Magnum Engine Issues?

1. Weak Transmission

Dodge models between 2000 and 2008 are known to have a transmission issue. The problem is associated with low transmission fluid levels.

Also, damaged torque converter, transmission software issues, insufficient fluid cooling, excessive towing, and bad gear clutches are some of the known causes of weak transmission in most engines. If you also fail to carry out the routine transmission servicing, you can also experience the problem.

Weakness in the transmission is largely due to a flaw in the design of the Magnum Dodge 318 engine. Using 46RH and 46RE transmission systems, the 318 Dodge engine is designed with a torque converter that can easily go bad.

Weak gearing ratios and vulnerability of transmission cooling lines to design-related conditions can cause driveability issues for 318-powered 4×4 vehicles.

The transmission of the 318 engine starts to give issue around 100,000-200,000 mile mark. Transmission issues should be a great concern because it requires a considerable internal upgrade or rebuild.

Symptoms Of Weak Transmission

  • Slipping Gear: Typically, a gear change occurs and comes into force and through some external input. While the driver chooses a gear shift in manual transmission, automatic transmission only requires the driver to select Drive (D), Reverse (R), or Neutral (N), or Park (P). Worn transmission lines could be responsible for the slipping in gear. Low fluids can also cause the gear to slip. You may also notice that the vehicle refuses to switch gears when the transmission is bad.
  • Burning Smell: Another critical symptom of a defective transmission is a burning odor from the car. When the transmission overheats or the transmission fluid is burning old. Besides, a low-quality or non-recommended transmission fluid burns easily.
  • Illuminating Check Engine Light: The check engine light of the Dodge 318 engine can come on if the transmission becomes weak or worn. But, I’ll advise you to let your local technician take a look at it and diagnose it to make sure what the problem is.
  • Grinding Noise: A failing transmission of an auto transmission engine like the Dodge 318 will cause the car to shake. When your car starts to get the shakes during a gear change, it’s time to inspect the transmission.

Other signs of a weak transmission include neutral noise, leaking fluid, humming sounds, unresponsiveness of the car, and more.

What Should You Do?

The truth is that the functionality of your engine transmission doesn’t come to a halt instantly. It takes some degree of neglected damage. When the signs keep coming and you don’t nip them in the bud, the transmission will pack up.

The cost of fixing a transmission problem can be as high as $5000, depending on the severity of the damage. Minor fixes such as topping or replacing burnt fluid, replacing defective solenoids, adjusting throttle cables, or re-calibrating for leaks can come on the cheap.

However, a major issue like replacing the entire transmission requires you to break the bank. You’ll need the service of an experienced local technician to fix this problem.

2. Broken Exhaust Manifold Bolts

Although not a design-related issue per se, having worn exhaust manifold bolts can be dangerous. When you hear a ticking sound coming from the engine bay, then the exhaust manifold bolts may be loose or have broken.

This is common to any engine. By design, the exhaust pipes of your engine are firmly joined to the cylinders, thanks to the exhaust manifold bolts. The exhaust pipes are essentially designed to gather burnt air and send it out into the atmosphere.

The Dodge 318 5.2 Magnum engine has seen many of its users complain about the noise. While it was initially thought to be a lifter tick, the ticking noise was found to be a result of loose bolts holding the exhaust manifold to the cylinders. When these bolts break, air will leak away, causing the ticking noise.

The consequence is felt on the engine because the catalytic converter needs to burn the engine gas before it escapes to the atmosphere. If not used or burnt, the escaping gas will cause several issues, ranging from a ticking noise to a decrease in performance.

Symptoms Of Broken Exhaust Manifold Bolts

  • Loss Of Acceleration And Poor Performance: Generally, any problem with the car engine is likely to cause poor performance. More specifically, when the exhaust manifold bolts break, it causes the cylinder to separate from the exhaust manifold. The consequence is that the engine will start to perform poorly and lose acceleration.
  • Engine Bay Gives Off Ticking Noise: The ticking noise from the engine bay area is one of the earliest and most noticeable signs that your exhaust manifold bolts are loose or broken.
  • Croaky Exhaust Noise: Another sign that your exhaust manifold bolts are broken or defective is the raspy noise that the exhaust releases. When you observe a louder exhaust note or hoarse sound from the exhaust area, you can suspect loose ends between the cylinder and the exhaust manifold.
  • Decreased Fuel Economy: A decrease in the amount of fuel your car consumes is also another symptom of failing exhaust manifold bolts.

What Should You Do?

When you notice these signs and trace the root to broken or loose exhaust manifold bolts, the thing to do is to replace the bolts. The costs for part purchase and labor are fortunately affordable. Something in the region of $200-$250 will fix the problem.

In the same way, the procedure for the replacement is also pretty simple and seamless. Additionally, you should inspect the exhaust manifold gasket to know if it is damaged due to exposure to open air. If damaged, you should replace the gasket to avoid further deterioration.

3. Camshaft Sensor Failure

Dodge 318 engine problems can also come in the form of a failed camshaft position sensor. The role of the camshaft position sensor is to take the readings of the speed and place of the camshaft in the engine.

The electrical control unit receives the readings taken by the sensor and uses them to control the amount of fuel that should go into the combustion chamber for complete combustion to take place.

Ideally, a sufficient amount of fuel must be burnt by the chamber at the right time and the camshaft position sensor is directly responsible for regulating the ignition timing to prevent surplus or deficiency in supply. A bad cam sensor can cause the ratio of air to fuel to get out of hand, leading to performance-related issues.

However, the sensor can fail or get clogged. When grime, gunk, dirt, or dust accumulates on the sensor over time, it will start to malfunction before it will completely break down.

The result is that it’ll send inaccurate readings to the ECU which in turn over or under-supply the amount of fuel that gets into the combustion chamber.

Symptoms Of Failing Cam Position Sensor

  • Rough Idling: Driveability issues are one of the immediate signs that your camshaft position sensor is faulty. It starts with a few irregular performances that range from rough idling to frequent stalling, loss of power, slow acceleration, frequent stumbling, and decreased fuel economy. When you notice these signs, you should suspect that your cam position sensor is gradually giving way.
  • Check Engine Light Illuminates: Although there is a wide range of reasons your car’s check engine light can come on, a bad camshaft position sensor is the top sign. What you should do when in doubt is to have the car inspected by a certified technician to carry out an ECM scan for any error code.
  • Hard Or No Start: Even if you ignore other signs, you won’t do it when your car fails to start. The weaker the CPS gets, the faster the car’s ECM receives signals and also becomes weakened. The signal will shut down eventually after a long period of negligence.

You may also notice signs such as cylinder misfires, poor car performance, loss of power, rough idling, and P0340 and P1391 codes.

What Should You Do?

The first thing to do is to try to see if you can unclog the sensor by cleaning the dirt, grime, or gunk build-up. If this approach turns out to be the magic wand, that’ll mean that the sensor hasn’t got any serious damage. If it doesn’t, then replacing the entire component will be the last option.

Even if you’ll have to go for a new sensor, you won’t have to break the bank. Something in the region of $50 will buy you a new sensor. If you find a Do-It-Yourself fix a little bit cumbersome and time-consuming, labor cost is also affordable, something in the region of $250 and $400.

4. Plenum Gasket Issue

To some degree, the plenum gasket also functions as the intake manifold gaskets in that they both seal engine vacuum. However, because of the location in the engine, the plenum gasket is more prone to wear and tear and can damage more easily than other gaskets.

Specifically, the plenum gasket serves as the link between the manifold and the plate. It welds the plate together with the intake manifold. The plenum gasket, like other gaskets, is an essential component of a car engine. The gasket is also responsible for capping the engine coolant to prevent leaks.

Made of a wide range of materials, including rubber, metal, or paper, the plenum gaskets are designed as seals in-between different engine parts to provide firmness. Some manufacturers design the gaskets from the combo of the three materials.

However, if the plenum manifold gaskets crack or crash, they give off some signs that the driver needs to pay closer attention to.

This failure will affect the correct ratio of air and fuel that the cylinder needs, causing the engine to receive far less than enough energy for power generation.

There are other symptoms you’ll experience once the plenum gasket fails.

Symptoms Of Failed Plenum Intake Gasket

  • Coolant Leak: Since the plenum manifold gasket is built into the engine system to seal the vacuum in-between the cylinder head, any damage to the seal will automatically result in and the coolant leaking away.
  • Low Coolant Economy: The natural consequence of a coolant leak is a low coolant economy. What’s even more sapping here is that you’ll have to visit the gas station more often than normal.
    Besides, because the failing plenum gasket is not able to seal the vacuum in the engine, the rate of coolant consumption increases, causing inefficiency in coolant use.
  • Engine Stalling: Slow turning of the engine or its refusal to turn is a natural consequence of a vacuum leak which is caused by plenum gasket failure. This in turn will lead to stalling, making the engine shake. Once the ratio of air to fuel becomes irregular and abnormal, drivability issues arise.
    Since engine stalling can result from different issues, you should call on a certified mechanic to carry out a vacuum leak test to ascertain the source of the problem.

Other noticeable symptoms include loss of acceleration, increased fuel consumption, engine overheating, and more.

What Should You Do?

Prevention will be a lasting cure. However, since a plenum intake manifold gasket, like other components of the car, can damage due to old age, use, mileage, and wear and tear, there are things you can do to fix or replace the part.

Replacing the gasket including the cost of the gasket and labor cost will be something in the range of $300-$500. A DIY method isn’t advised.


1. How Reliable Is The Dodge 318 Engine?

Absolutely! Fortunately, there is a lot more that defines the Dodge 318 5.2 Magnum engine than these apparent problems. When it comes to reliability, this solid engine – whether in its first, second, or third-generation – ranks atop many of its competitors out there.

First off, the Dodge 318 engine doesn’t come under any of the costly engine issues that plague many other engines. Common critical issues, such as cylinder head cracks, frail internal components, carbon-build, spark plugs failure, or ignition defects do not come close to this fairly solid engine. Apart from the plenum gasket defect and transmission weakness, this engine is good to go.

2. How Long Can The Dodge 318 Engine Last?

The longevity of any machine is based on a wide range of factors. From maintenance to mileage, strength, and durability of the constituent parts, the life expectancy of an engine can be determined.

When it comes to the strength of the parts, the dodge 318 is fairly durable. On average, too, the engine can last onwards of 300,000 miles or 20 years.

3. What Are The Specs And Metrics Of The Dodge 318 Engine?

Metrics: Specs:
Carburetor Two-Barrel
Horsepower 230 @ 4400 rpm
Torque 340 ft-lbs @ 4400 rpm
Compression 8.6:1 (Initially 9.1:1)
Stroke 3.312-inch
Bore 3.91-inch
These specs vary based on the year of production. Earlier models, especially first-generation engines, have higher compression ratio but this was reduced to imrpove fuel economy.

Final Thoughts

As you have noticed, the Dodge 318 engine problems I have identified here shouldn’t scare any car owner, driver, or technician who truly cares about their car.

Plenum gasket leak, camshaft sensor failure, weak transmission, and ticking noise due to failing exhaust manifold belts are not issues outside of this world. They are located in many other engines there.

What I suggest –and this is normal –is to take serious preventive measures to arrest some of these issues at the earliest stages of their development before they escalate or cause further damage. Think about it, you cannot over-care for your assets. After all, your convenient mobility shouldn’t be priced.

Here’s the final appeal I will make: do not fix without a diagnosis. The reason is simple. Most automobile-related issues have interrelated symptoms, and unless you carry out an in-depth scan of the problem, you may end up implementing a completely wrong solution for a non-related problem.