The camshaft plays a critical role in the functioning of your car engine. It ensures that the cylinders fire correctly and at the correct times. The camshaft also ensures that cylinders fire in perfect synchronicity with one another.
When a camshaft goes bad, look out for 6 tell-tale signs, including an illuminated Check Engine light, engine misfiring, excessive emissions, and some noises. The most telling are metal bits in the engine oil and visible damage on the camshaft itself.
Figuring out if your camshaft is bad can be challenging if you're not familiar with it. This guide will help you with that. As you keep reading, you'll understand what a crankshaft is and what it does before we dive deeper into signs that your crankshaft is going bad.
What's the Difference Between Crankshaft and Camshaft?
Like most people, you’ve probably confused a crankshaft and a camshaft at least once in your life. So, before we continue with this guide, let’s resolve the crankshaft vs camshaft confusion first.
What’s a Crankshaft, and What Does It Do?
You’ll find the crankshaft at the bottom or base of the engine, where it is positioned like a backbone.
During the combustion process, the engine’s pistons move up and down, rotating the crankshaft. In other words, the crankshaft converts the vertical piston movement (up and down) to a horizontal rotational movement.
The crankshaft then channels power to the gearbox to turn the vehicle’s wheels.
What Is a Camshaft, and What Does It Do?
Unlike the crankshaft, you’ll find the camshaft at the top section of the engine. It’s also a rotating rod (aka shaft) but has several cams, which are irregularly-sized lobes rotating with the shaft.
As the camshaft turns, the cams will press down on spring-loaded valves, activating each engine cylinder's intake and exhaust valves. Manufacturers design the camshaft to perfectly synchronise the triggering of specific valves.
The camshaft also has a crucial component called the camshaft position sensor. The camshaft sensor lets the engine’s computer know the precise position of the cams so that it can time the firing of each cylinder with incredible precision.
The rest of this guide will focus strictly on this camshaft and not the crankshaft, which serves a different purpose altogether.
What Are the Symptoms of a Faulty Camshaft?
Now that we’re crystal clear on the camshaft’s function, let's look at the symptoms of a camshaft that isn't working correctly. As with other malfunctioning car parts, the symptoms include warning lights, bad performance, and even a few unusual noises.
6 Signs of a Camshaft Going Bad
Here are 6 signs that your camshaft is going bad:
1. Check Engine Light
Ah yes, the good ol' Check Engine light. As you might already know, this light isn't always so helpful. That's because a long list of different engine issues can trigger the light to turn on. At first glance, it's unclear if the light is related to the camshaft.
Still, you can consider the Check Engine light a vague indicator of a camshaft problem. So, as you troubleshoot that light, it’s worth considering that the camshaft might be what’s causing it to turn on.
2. Misfiring Cylinders
Another sign of a camshaft problem is misfiring in the cylinders. Remember: the camshaft is responsible for timing the combustion process in each cylinder. So, it stands to reason that a problematic camshaft will manifest itself in the form of misbehaving cylinders.
When misfiring happens, your car will shake, jerk, and even hesitate when you try to move it.
3. Emissions Getting Worse
When the combustion process doesn't happen smoothly, and cylinders start misfiring, you'll also get worse exhaust emissions. Of course, this isn't always the most noticeable sign. Still, it's worth checking if you suspect the camshaft isn't working correctly.
4. Noises
Thankfully, there are some signs of a bad camshaft that are easier to notice. For instance, bad camshafts will cause tapping and ticking sounds to come from the engine.
These sounds might be noticeable to you while in the driver’s seat. However, you’ll likely have to open the hood and listen closely to be sure.
5. Contaminated Engine Oil
Mechanics and car enthusiasts will know that it's a terrible sign if they see engine oil contaminated with metal pieces. The only way that metal debris finds its way into the oil is if two parts are grinding against each other in ways they should not.
That scenario will happen when you have a bad camshaft. So, even if you don't notice any other symptoms, this one should cause you alarm. So, troubleshoot the engine and rule out the camshaft as soon as possible.
6. Visible Damage on the Camshaft
The last and most obvious sign that you’ve got a bad camshaft is when you see visible signs of damage on the part itself. So, of course, this would be the most direct way of confirming that you have a camshaft problem.
However, it’s also the most challenging because you’ll have to open the engine to get to it.
Can You Repair a Bad Camshaft?
The honest answer is 'It depends.' The first step is to inspect the camshaft very closely to see whether someone can rebuild it. Of course, that person must have the necessary tools and skills.
You can only rebuild a bad camshaft if:
- The camshaft is still straight.
- The camshaft only has minimal wear.
- The case hardening depth is still acceptable. The cams have a more rigid outer layer and a softer inner layer. When the rebuilder works on it, they'll have to grind into the stiffer outer layer, and that's only possible if there's still enough of a hard exterior to grind into.
If you can’t rebuild the camshaft, you’ll have to replace it with a new one.
How Much Does It Cost to Replace a Camshaft?
You can expect to pay anywhere from $200 to $500 for a new camshaft. The final camshaft price will depend on the type and quality of camshaft you choose. The price will also include any gaskets and seals that go along with the camshaft.
Naturally, a high-end performance camshaft will likely cost you more than standard pieces.
If you’re in the market for an Aussie-made camshaft, there’s no shortage of excellent suppliers you can choose from. You can get a Crow camshaft, a Tighe camshaft, or even a Camtech camshaft, among other high-quality Australian brands.
You can shop for used or new camshafts over at Carpart.com.au. Start by checking out the Marketplace for the best deals on used parts.
If you're in the market for a new camshaft, submit a request through the Part Finder. That request will go out to suppliers across Australia who will return to you with the best prices.
By Ray Hasbollah