Hey Scotty I know you’re not a fan of boxer engines particularly the 6 cylinders but I was wondering what your opinion is on the turbocharged 4 cylinder in the WRX? Is it just as reliable as the non-turbocharged 4s? Are there any particular problems you’ve seen with them?
Turbocharging brings with it additional complication and service issues. Aside from the turbocharger itself being an expensive part to fail that can be difficult to replace, there are additional oil and coolant lines involved, as well as other components that can fail. So over the long haul it will be more expensive to run than a normally-aspirated mill. However when taken care of, turbocharged engines can last a long time. My turbocharged car is just fine after 24 years and nearly 360,000 miles. However, the previous owner did replace the turbocharger at around 200,000 miles.
One thing to note as well is the WRX’s engine (FA20DIT) is direct injection only and will be susceptible to carbon buildup over time like most GDI engines.
I think in that clip he was referring to the longevity of the naturally aspirated 4-cylinder versions, not so much the turbo charged ones.
Scotty is slowly coming around on Subaru; the infamous head gasket problems are mostly in the past and the newer Subaru motors are pretty well sorted (... though the CVTs are another matter).
I agree with Chuck that the turbo adds complexity and will always be less reliable than an equivalent NA motor. It also adds strain to everything down the power train. Speaking as a WRX owner who has a vested interest in knowing what problems they have, I haven’t really seen anything major reported on the current FA20DIT. Assuming it’s unmodified, long term reliability should be fine.
