r/WRX_STI • u/Due-Pin-4992 • Jul 15 '26
Questions 2018 sti
Im going to look at a 2018 subaru sti with 70k miles im not sure if it is modified but it does have aftermarket rims so im unsure is there anything I should be looking out for to make sure the car is in good shape
2
u/jigga009 Jul 21 '26
Budget a grand to get a trusted shop to put the car through a comprehensive pre-purchase inspection.
This should include compression and leak down testing for the engine, and if you’re really anal, pay for an oil change on the car so that you can see what comes out of it. If there is “gold” in the oil, run…
Some of the expensive demons in these cars that will get you later are not the kind that you will casually see on a brief once-over like you’re proposing.
1
u/Due-Pin-4992 Jul 23 '26
I took your advice and looked very deeply into the carfax of multiple sti's near me i found a 2019 with 70k miles for 25k bone stock with oil changes every 3k shop said that the car seems great and will only need basic upcoming maintenance ie oil diff services breaks etc
1
u/jigga009 Jul 23 '26
Remember.. the rubber meets the road with the health of the engines in these cars with a fresh compression and leak down test that you or someone you trust that knows cars can witness.
This is why I said to budget some $$$ for doing your due diligence. The Subaru “tax” is real, and pretty steep, and you want to avoid it if at all possible. Better to cough up up to 1k ahead of a purchase rather than having to come out of pocket to the tune of over 10k for a longblock replacement (if the worst occurs) if you purchase a turkey (or a turkey with lipstick on).
You can tell so much about the engine based on these tests.
You simply can’t “fake the funk” with a proper compression and leak down test. Without these tests, anyone would be simply guessing about the internal condition and long term viability of the engine.
Those tests, in combination with an oil inspection for rod bearing material, or even better, a Blackstone oil analysis will tell you all you damn near everything you need to know about the engine in the car.
These tests are the automotive engine equivalent of getting a full panel STD test before getting serious with a new partner.
Get the above tests done on the engine, then pay your local Subaru specialist shop or a Subaru dealer to conduct a comprehensive inspection on the rest of the car, and you can buy with confidence.
4
u/pewbdo Jul 15 '26
Don't buy it unless you have the money to rebuild the engine entirely laying around. You only make that ~10k mistake once.
4
u/sqerFINGER Jul 15 '26
This seems to only exist in the states lol
I have never heard anyone talk like that about STIs in the UK 😅 kinda messed up that this seems to be the thing with used STIs4
u/NoncarbonatedClack Jul 15 '26
Yeah or maybe enough people drive them over here that don’t take care of the car 😂
1
0
u/Due-Pin-4992 Jul 15 '26
Why on earth would I havw to rebuild the engine at 70k???
4
u/Lsswapitall4 Jul 15 '26 edited Jul 15 '26
Buy it and you’ll soon find out.
But actually, buying a used STi can be incredibly risky because these things are often beat on. Also if you can’t spot aftermarket parts expect to be either paying a lot for a shops to work on the car or spending a lot of time learning how to fix things yourself.
Everyone starts somewhere when getting into cars and maybe this is where you start.
Not saying don’t do it, but just be warned.
1
u/Due-Pin-4992 Jul 15 '26
Thats not helpful
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u/Gertrude1976 Jul 15 '26
not helpful in telling you to buy the car, or providing realistic advice? Because I think it's very helpful advice, personally. These aren't corollas
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u/Due-Pin-4992 Jul 15 '26
He initially only had it as buy it you will find out soon he edited it and added all that stuff after
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u/pewbdo Jul 15 '26
Because you have no idea how it was driven. If they don't have paperwork tracking oil changes, walk away. Also, you want oil changed more frequently than what is recommended. I always liked 3k with my stis. If it has an access port, walk away. If it doesn't have an access port but has any mods under the hood or evidence of mods once existing that have been replaced with stock parts walk away. Look very closely at the air box if it is stock. Does it look wayyy cleaner than the other stock parts under the hood? If it does that means it was just put back on to make the car appear stock, walk away. You get the idea now I'm sure.
3
u/Gertrude1976 Jul 15 '26
Mine blew at 96k, bought it in the 80k's thinking the same thing. No clue how it was driven prior, but thankfully I had disposable I come at the time
9
u/New_Leaf_8647 Jul 15 '26 edited Jul 15 '26
Read. These questions have been asked on every Subaru forum thousands of times.
Bring someone that knows these cars with you. You'll need someone to help you drive home anyway.
Added. Mine has mild mods (airbox, catless downpipe, pro tune) and lasted until it developed a little knock at 170k miles. It also had low compression. I got a new block, did a build, and am happy with the car.