Considering 2018 Subaru Impreza STI?
 

Been looking around for a vehicle to possibly replace the worthless and unreliable 2014 Hyundai Azera daily driver I sold because the transmission failed and it had a exhaust manifold gasket leak. I am considering purchasing a 2018 Subaru Impreza STI as I had a 2003 Subaru Impreza WRX 2.5L four cylinder turbo that lasted 351K miles when I traded it in and it still ran well. I am looking for something that is reliable and dependable yet sporty and fun to drive every day? I have seen some of the guys at the track running high 13’s and low 14’s at around 99-105 mph in stock or almost stock trim. Any thoughts on the new 2018 Subaru Impreza STI? Any current or ex Subaru owners here? How does the 2018 Subaru STI really compair to the 2018 Nissan 370Z?

Either be prepared to reflash the ecu immediately (and deal with any potential warranty headaches) or stay away from the turbo 2.5. Subaru programmed a nasty lean spot on spoolup to meet emissions targets. That's why so many of them break ringlands. Either get the wrx with the 2.0 or be prepared to get it tuned immediately after the break in period.

Thank you sir for your valuable advice. The tune that Subaru put on the STI is quite inferior as you can’t do any modifications to the engine without it leaning out the engine it’s pretty sad. The only modification Subaru’s tune can compensate for is a high flow air filter like a drop in K&N high flow air filter etc. pretty sad. I had a ultra conservative Cobb Tuning stage 1 tune on my 2003 Subaru WRX I had that would explain why my engine lasted so long and kept going strong. Since the only thing you can do is get the STI tuned which possibly could compromise your Subaru warranty on your engine ecu or deal with warranty claims on the 2.5L engine or not purchase a new STI it sounds like Subaru puts your back up against the wall. Chuck how much mileage do you recommend going before the engine break in is done? What tune or what software would you recommend using?

It's not an issue about it leaning out when you add mods. It's the factory tune. Your 2003 did not have the same problem since they had a decent tune stock and kept emissions in check during spoolup with a cat in the uppipe. You could actually get away with a full catless exhaust on a 2002-2003 motor with zero issues. This issue started around 2008 or so. If you're ok with the potential warranty problems, give it 1k miles and reflash it. Otherwise wait until they do something about that motor. Personally, I'd stay away unless you're planning on such heavy modding that the warranty would be worthless anyway.

I do agree Chuck I have talked to a Subaru technician before he said that the tolerances on the 2.5L engine is tight and piston rings seat quite quickly and to not go over 4K rpm for the first 1K miles or floor the accelerator pedal for the 1st 1K miles for proper break in of the engine. I would tune the vehicle immediately after the first 1K miles and perform an oil change.

Good research here linked. Both stock or with modifications. My STi provided no issues at all. Was a new 2015 sold after 2 years. Wonderful machine. On many days I do miss the car. The STi is a nice package and demands your attention to drive well.

Other A positive thread-STi's WITHOUT issues - Subaru Impreza WRX STI Forums: IWSTI.com

I miss mine all the time. I had it for years, modded the hell out of it, drove the hell out of it and never had any problems. I sold it to someone and they blew it up in three weeks after doing exactly what I told him not to do. I should have found a way to keep it.

I traded in my '03 WRX for my ZR. Mine was a 2.0L. Did you swap out your stock 2.0L for a 2.5L engine? My WRX had Cobb Stage 2 :)

Personally, I don't really like the looks of the new '18 STi. But the engine is proven and as you probably know, has lots of aftermarket support.

I believe the body style of the 2018 Subaru STI is quite nice. The aftermarket for the 2018 Subaru STI is well supported. On the 2003 Subaru WRX I had I did the 2.5L engine swap it was involved but well worth it. As stated I did a ultra conservative Cobb Tuning stage 1 it was very reliable. As Chuck stated there is a fix for this issue with the STI.

I miss the 2003 Subaru WRX I had also but it was just time for something newer really. The guy I sold it to ended up turning it into a track car and he took care of the vehicle very well. Out of all the vehicles I owned the 2003 Subaru WRX was the best most reliable/dependable. They are enjoying to work on as well as the Z is.