90 TSi always run on 87 octane - damage?

[Gregus]

I just got back from looking at a 90 TSi AWD I was thinking on picking up as a winter bomb. It's in decent shape and runs real nice. On talking to the owner though I found out he always ran 87 octane in it since he bought it in 93. He just didn't know any better.

Question is, could this have caused any damage running it like this for all that time? He never drove the car hard (he's an older guy) and it seems to run pretty good (not much power though when I test drove it for obvious reasons).

Anyone have any opinions?

 

[blcknspo0ln]

less octane = more knock, but if it was treated nicely, shouldn't have done too much damage

 

[Defiant]

It should be fine.

 

[hereitcomes]

it was probably pretty slow haha

 

[drivemusicnow]

I would expect (and i'm not POSITIVE that the dsm ecu does this) but that after a couple tanks of gas, it would give up on the 91 octane tune and just stay in a "safe mode" where it pulls timing and adds fuel... probably got pretty crappy fuel mileage, and no performance, but no damage whatsoever.

 

[Dsm 95 Tsi Awd]

this is from what i heard, so if i am wrong, please correct me that way i know:

they way i understand it is with turbos you need atleast 90 octane and if you have less, you get a lot of knock from predetination. Predetination is where it sparks either before or after (cant remember which one) before the piston has reached its highest point. so i know you get a lot of knock from not putting in gas with less octane.

but being that defiant said you should be fine, i trust him and i would go with what he said..

-alex

 

[wallyman]

Preignition doesnt even use the spark to ignite the fuel. The combination of low octane, high pressure, and high temperture ignite the fuel before the spark plug fires. But overall your concept was pretty close.

 

[Gregus]

Thanks all.. I appreciate the responses. Sounds like I should be OK.. just needs a good tank of high-test to get her back on track