Is a Subaru piston slap normal?
Yes, a certain amount of piston slap in Subaru engines is considered normal and not a cause for concern. Piston slap is a common phenomenon in many internal combustion engines, including those found in Subaru vehicles.
What is Piston Slap?
Piston slap refers to the audible noise that can occur when a piston moves up and down within the cylinder bore, causing it to momentarily "slap" against the cylinder wall. This happens because there is a small amount of clearance between the piston and the cylinder wall to allow for thermal expansion during engine operation.
Why Does Piston Slap Occur in Subaru Engines?
Subaru engines, particularly the boxer-style engines, are prone to some degree of piston slap due to their design. The horizontally-opposed cylinder layout and the relatively short connecting rods in Subaru engines can contribute to increased piston movement and the potential for piston slap. This is considered a normal characteristic of Subaru's engine design and not an inherent defect.
Is Piston Slap in Subaru Engines a Problem?
In most cases, the piston slap heard in Subaru engines is not a cause for concern and does not indicate a problem with the engine. As long as the piston slap is not excessive, does not worsen over time, and does not cause any other issues, it can be considered a normal part of the engine's operation. However, if the piston slap becomes significantly louder or more pronounced, it may be a sign of a more serious issue, such as excessive wear or damage to the piston, cylinder, or other engine components. In such cases, it is recommended to have the engine inspected by a qualified mechanic.
Tips for Dealing with Piston Slap in Subaru Engines
- Understand that a certain amount of piston slap is normal in Subaru engines and not a cause for immediate concern.
- Monitor the piston slap over time to ensure it does not worsen or become excessively loud.
- If the piston slap becomes significantly louder or more pronounced, have the engine inspected by a qualified mechanic.
- Maintain the engine according to the manufacturer's recommendations, as proper maintenance can help minimize piston slap and other engine issues.
In summary, while piston slap is a common occurrence in Subaru engines, it is generally not a cause for alarm unless it becomes excessive or worsens over time. By understanding the normal characteristics of Subaru's engine design and monitoring the piston slap, you can ensure your Subaru engine continues to operate smoothly and reliably.
What year does Subaru have a bad engine?
The performance-oriented Subaru WRX and WRX STI from 2008 to 2014 unfortunately did not escape their own set of difficulties. These cars were plagued with engine problems. Such problems included bearing failure in the EJ series of engines, leading to a major engine rebuild or replacement.
Should I be worried about piston slap?
The noise that piston slap produces usually clears up as the engine heats up. The piston expand and fit in the bores more snugly. The results of piston slap usually lead to increased wear of the piston, cylinder wall, increased oil consumption,, and eventually Catastrophic engine failure.
Can you get rid of piston slap?
The only way to fix it is to tear the engine apart and replace the piston rings. 99% of the time, the costs of repairing the engine exceeds the market value of the car. Just either replace the engine or buy another car.
Will thicker oil stop piston slap?
Generally, it will be worst when the engine is cold, and quieten down as it warms up. A thicker oil may help slightly, but creates other issues so is not really a great idea. Going from a 10W30 to a 10W40 would be OK, but probably won't do enough to matter. Over time as the wear gets greater, the noise will get worse.
What is the number one problem with subarus?
Transmission issues are the most common problem in Subarus, but defective airbags, faulty fuel pumps, weak windshields, and electrical issues are also known to happen. Subarus generally receive high reliability ratings, according to RepairPal. Transmission issues are the most common problem in Subarus.
Is it safe to drive a car with a piston slap?
I almost always recommend driving it until other problems surface. Heavier oil might be better for quelling piston slap, but you run the risk of not getting oil where it needs to be in a timely fashion. If you aren't running a full synthetic oil, this would be the only change I'd make.
What is the biggest problem with Subaru engines?
Oil consumption
Some Subaru engines have been known to consume excessive amounts of oil. This can be caused by a number of factors, including worn piston rings, a leaky valve cover gasket, or a failing oil pump. Symptoms of oil consumption include: Low oil level.
Can I ignore piston slap?
So in answer to your question... If piston slap is just ignored and left to slap away it can be very harmful to an engine, and yes it can be prevented/avoided. Or at the very least minimised.
Can you still drive with a piston slap?
I almost always recommend driving it until other problems surface. Heavier oil might be better for quelling piston slap, but you run the risk of not getting oil where it needs to be in a timely fashion. If you aren't running a full synthetic oil, this would be the only change I'd make.
Is piston slap worth fixing?
As we've discussed before, piston slap is usually a minor issue, but a very annoying one in terms of sound. Very rarely is it worth digging into the block to address the problem without doing a full rebuild.
