Hello S2000 Community. My Girlfriend and I or looking at a pristine 05 GPW S that has has passed mine and a shops inspection pretty solidly. While riding with the sellers husband he mentions that she has been running regular unleaded in the car because she couldn't feel a difference. My short stint in my local community collages ASE program tells me that is a definite no no in a car with 11:1 compression. The husband couldn't tell me how long she had been using regular so this could have been happening for years. The car is otherwise fine with a few other very minor issues and I want to pull the trigger but now I'm wondering if I may be getting myself into a rebuild or new engine in the not so distant future. Anyone on this forum have experience with the long term effect of running too low octane fuel in the S2000? Should I pass on this S?

 

I'm not a mechanic and I never use less than premium unleaded - but modern computers (ECU) usually can adjust the timing allowing the engine to work with a lower octane. Did you hear engine knock when driving it?

 

Thanks for your reply. No, I did not hear any Knock and I am aware of the ECU's abilities but I thought it was more for a mistaken mis-fill situation (I dropped out of the ASE program due to the automobile electronics side,a so I could definably be wrong). It sounds like this woman my have been doing this for quite some time.

 

I would pass on this S. There are a few things this car requires maintenance wise and the fact that they ignored one of the biggest things should be a hint as to how they maintained the car during their ownership.

 

I would never even consider it if it's been done on a regular basis. The ECU can pull timing but I don't know how much it can handle. Long-term if it's been detonating regularly then the crank and rod bearings are going to have taken a beating.

Also consider this: if someone is willing to cheap out just to save $100 a year on gas vs. buying the correct octane fuel, what else have they cheaped out on in regards to care and maintenance?

 

just change the fuel an drive it...I am imagining you drove it.. got vtec up an screaming.. did it act like it knew a difference... then you were told.. if the cars priced right, if this helps lower that price maybe.. idk what to advise you.. but if it met all the basic for what I wanted.. change the fuel an enjoy..

 

I would guess that this S was rarely, if ever, driven hard. Sounds like the owner enjoyed it as a cruiser. I wouldn't be concerned about the type of gas used. My Dad runs regular gas in his Avalon that Toyota says should have premium. Does he get the best performance out of it? Probably not. But he doesn't drive it hard and the ECU is compensating for the lower octane. If you like this car, buy it, and treat it to premium. The ECU will readjust and it will be fine.

 

Thanks for all the replies everyone. Normally I would be on that same train of thought as baZurk but there are reasons I am not trusting my usual judgment with this car. First the owners are up in age and claim they have driven the car lightly for its 30,000 miles(which I believe). The car is otherwise in very good if not excellent condition. The paint is great, the under carriage looks good, the interior looks almost new, the usual signs of carless ownership are not there. The other problems are minor, like curb rash on three of the wheels (older female driver), Weak battery (car only driven once or twice per month), minor moisture in the break fluid (car only has 30000miles so prob never changed). All things considered I believe it is a simple case of ignorance on the part of the seller, I'm just worried about any long term affects. I guess that I'm on the fence and look for a push in one way or the other. I really want to buy but I'd hate to get it home and start exspereacing knock

 

How many miles on it? A lightly used, low miles car should be considered. I would take it to your mechanic for a professional opinion though.

Good luck.

 

doesn't sound like it's been cared for in general...pass