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Which fuel do you use?
Joined: Jul 2004
Posts: 3,295
From: Austin, TX
RE: Which fuel do you use?
if your not chipped then it shouldnt matter what octane you use. especially if you have a v6. the sudi v6 can run fine with 87 octane because it doesnt require the knock protechtion that turbo cars do
4th Gear
Joined: Jun 2004
Posts: 4,151
From:
RE: Which fuel do you use?
Look at your combustion chamber, the lower octane gas combust to fast.It will ruin your spark plugs. And its not good for your cat and o2 sensor.You will be paying the differnce in repairs useing 89. But hey, dont take our word for it, you'll find out soon enough.
btw- flip your gas tank lid open and read, if you still think 89 is ok
btw- flip your gas tank lid open and read, if you still think 89 is ok
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2nd Gear
Joined: May 2004
Posts: 1,096
From: Indianapolis, IN
RE: Which fuel do you use?
On an unchipped 1.8t the ECU can retard the timing somewhat in response to the use of lower octane fuel. The problem, as I see it, is this. With the requirement from Audi that we use at least 91 octane fuel, the engine is tuned such that the timing is advanced to provide higher performance. By using a lower octane fuel you are doing two things. One, the lower octane fuel combusts too soon so you are dumping unburned fuel into your cat and over your 02 sensors. Two, the ECU, sensing the early combustion (knock), retards the timing and lowers the overall performance of the engine. Also keep in mind that when your ECU retards the timing in response to knock it also curtails the amount of boost your turbo produces which defeats the purpose of the engine design in the first place. JMHO