This is Why Your Subaru is Overheating

If your Subaru overheats, you’re not alone. While Subaru has a long history of making sturdy, reliable vehicles, the head gasket on some models is a weak spot. The most commonly effected Subarus are Impreza, Legacy, and Outback models produced between 1999 and 2004. The 2.5L SOHC engine powering these cars had a poor head gasket design.

Your car’s head gasket circulates the coolant through the engine to prevent it from overheating. That means a faulty head gasket can lead to the motor overheating.

If your Subaru is in this model range and is overheating, it probably needs a new head gasket.

Telltale Signs Your Subaru Engine is Overheating

  • The needle on your temperature gauge creeping into the red zone
  • White smoke coming out from under the hood and/or the tailpipe
  • A burnt, sweet smell coming from the engine
  • Sluggish acceleration

White smoke

White smoke is one of the symptoms of an overheated engine, via Ruben de Rijcke

How Do You Know If It's the Head Gasket?

So you know for sure that your Subaru is overheating. Now it’s time to pinpoint the culprit. Since a blown head gasket is the most common cause behind engine overheating, it makes the most sense to check your head gasket first.

Here are the symptoms of a blown head gasket:

  • Loss of coolant without any noticeable leaks
  • Black-colored coolant in the recovery chamber
  • Water leaking from the exhaust pipe* (see note below)
  • A milk-like ring around your oil cap
  • Motor oil that looks like the color of coffee with creamer
  • Coolant spraying out of your spark plugs’ holes
  • Cracks or holes in one or both of your head gaskets

*NOTE: A small amount of water leaking from a tailpipe can be normal. Water is one of the byproducts of combustion, and people living in colder climates will often see water dripping from their exhaust. So, if your only symptom is water leaking, it could just be normal condensation.

Damaged gasket

A damaged head gasket, via Lewis Collard

Replacing Your Head Gasket

If the head gasket has failed on your vehicle, replacement will cost you $1500-$3500 dollars at your local shop. That's because it involves removing the top-end of your engine, which is time consuming and intimidating. However, head gasket replacement is fairly straightforward if you're mechanically inclined. If you have the tools and the time, a DIY replacement is perfectly feasible. This video (which - fair warning - has some profanity) walks thru the process step by step:

The cool part, of course, is that the gasket itself is very affordable. An OEM head gasket costs about $50 (or $35 from Subaru Parts Plus). Just clear your schedule for a weekend (or two), grab your tools, and have at it.

Good luck!