pakboy

I'm new to this website having just got my 2000 1.8t recently and I'm sure you guys have discussed this before. Is there a noticable difference between using regular gas and premium. I rather not pay $2/gal for gas if I don't have to.

Bob

1.8tqms
santorin blue/ecru

eharleq

Diesel has even more energy, best cost/performance ratio.

James R.

more carefull how you word replies like that...some people in this world aren't all that swift and might put Diesel in their car thinking that there is a chance that it would work out well.

Anyhow I hope he knows the diff...but just in case this warning might be in order.

Regards,

James R.

99 1.8TMS (Neuspeed K04, 5 Bar FPR, Beru Ultra X Plugs, K&N Filter, Remus Exhaust, S4 Wheel Well Liner Mod, Bilstein Sport Shocks, Neuspeed Sport Springs, Neuspeed Front Anti Sway, Brembo Rotors, Mintex Red Box, Ronal R-7's 17", 225/45/R17 Bridgestone S02 PP, Smartire (neat gimmick), Greddy Turbo Timer, European Projectors, Clear Sides and Full Tint...)

Ray Khan

<p>rakha

El Cucuy

<p>parkerpt
99.5 Light Silver/Opal Gray 1.8T qms

pakboy

Thanks for the diesel tip. I'm getting a tankful tommorow right after I polish my car with extra fine steel wool--I heared that works weel too. Please continue to post your excellent technological advice.

Ray Khan

for a 1.8T, regular 87 will do. For a 2.8 I would use the 90+ octane. Octane is a rating of how combustible the fuel is. It has nothing to do "cleanliness" which some people think. The bottom line is if you hear your engine pinging or knocking, start using higher octane fuel. When it comes down to it, it's about $2-3 extra per fill-up for the 93 octane stuff (compared to the 87 octane). Depending on how you drive that's probably $100-$400 a year. What's it worth to you?<p>rakha

Steve Y.

Always use at least the octane that the manufacturer recommends

James R.

I hope you didn't take my comment the wrong way...I wasn't trying to imply that I thought you were stuipid. I just think the way he wrote that reply would suggest that Diesel was an option.

As for gas quality...I'd pretty much stick to 92 Octane or better. The A4 1.8T has an extremely high static compression ratio for a turbo charged engine 9.5:1 on top of this there is the issue of deposits forming...something this engine also seems to be prone to. Therefore it would be in your best interest to use a higher octane fuel to eliminate the chance of pinging. The car will protect itself from abuse...it has dual knock sensors and independent ignition timing for each and every cyl. The real issue lies in the fact that if you use say 87 Octane on a daily basis...especially during hot weather you'll find (if you have a VAG) that the car is running with the timing more retarded than one which has run 92 on a daily basis. Basically what happens is the car will detect the pinging caused by using poor gas...as a result it will back off the timing thus eliminating the pinging. Cool it protects itself from damage...but at what cost, ultimately performance, grossly retarded timing does not make for good performance.

If you allow the car to ping frequently the car will adapt long term to a timing trim which is retarded more than the car would be at if run stock with 92 fuel. Now if you think you could just fill up with 92 whenever you feel like it you've got another thing coming...the LONG TERM timing trim will negate any benefits you might have gained by using the higher quality fuel. The only way around this is to reset the ECU...or continue using 92 on a regular basis so that the long term maps adapt to the higher grade fuel.

So you make the decision...for best performance use 92 or better...to save 15~20 cents a gallon use 87, but realize that it comes at a cost. BTW - Don't try to compare 92 and 87 back to back by running a tank of each and then deciding that 87 is fine...it takes some time for the maps to adapt...there will be more pinging initially with the 87 cause the maps are adapted to higher grade fuel..it takes a while to undo this. If you want to compare, drive on 87 for a few weeks...then fill with 92 and reset your ECU then go for a drive...holy ****, feels like a different car!!! This is even more true of a chipped car which places higher demand on the ignition control system..ect ect.

Regards,

James R.

99 1.8TMS (Neuspeed K04, 5 Bar FPR, Beru Ultra X Plugs, K&N Filter, Remus Exhaust, S4 Wheel Well Liner Mod, Bilstein Sport Shocks, Neuspeed Sport Springs, Neuspeed Front Anti Sway, Brembo Rotors, Mintex Red Box, Ronal R-7's 17", 225/45/R17 Bridgestone S02 PP, Smartire (neat gimmick), Greddy Turbo Timer, European Projectors, Clear Sides and Full Tint...)

cen

However, this does not seem to be the prevailing opinion on this discussion board.

Unless you demand maximum performance, as it seems many here do, I would consider premium to be a waste.

If things run the way they usually do, some of the arguments are that if you use regular, you are relying on the anti-knock sensor to keep the engine running right. I believe that this is true only for heavy loads and transient conditions, and otherwise, if the engine is tuned properly, it should not knock anyway.

Then people will say that the fuel access door says to use premium, but the manual says that this is not required.

Charles Norona