Hi Everybody,
I just joined this forum, although I own my TJ for quite some time. It is my second one actually, I bought my first TJ in 1998 in Germany and this one about three years ago here in Australia. I never had any issues, except only recently when I switched to ULP 91 octane. I was using that kind of fuel in Germany without any problems. I tried E10 for some time (it has 95 octane here in SA) and it was OK'ish). The manual (that's one from the 2004 model) says:
"Your engine is designed to meet all emissions regulations and provide excellent
fuel economy and performance when using high quality unleaded gasoline having
an octane rating of 87. The use of premium
gasoline is not recommended. The use of
premium gasoline will provide no benefit over high
quality regular gasoline, and in some circumstances may
result in poorer performance."
My idea was that the 91 octane fuel should be just fine, however the engine is knocking quite a bit. I asked a mechanic and he said that I have to use premium 95 or even 98 octane, no matter what the manual says. The manual on the other hand says the use of premium may result in poorer performance.
I'm somehow at a loss now; how could premium fuel result in poorer performance? And what fuel does the Wrangler actually need? Or is it that the fuel in SA doesn't have 91 octane but actually less? Maybe we get ripped off, I'd not be too surprised...
Or maybe the knocking is not normal and something else maybe the culprit? I'd like to stick to the 91 octane fuel, we wouldn't get any premium fuel in the outback anyway. Any advice?
Cheers,
Andreas
I just joined this forum, although I own my TJ for quite some time. It is my second one actually, I bought my first TJ in 1998 in Germany and this one about three years ago here in Australia. I never had any issues, except only recently when I switched to ULP 91 octane. I was using that kind of fuel in Germany without any problems. I tried E10 for some time (it has 95 octane here in SA) and it was OK'ish). The manual (that's one from the 2004 model) says:
"Your engine is designed to meet all emissions regulations and provide excellent
fuel economy and performance when using high quality unleaded gasoline having
an octane rating of 87. The use of premium
gasoline is not recommended. The use of
premium gasoline will provide no benefit over high
quality regular gasoline, and in some circumstances may
result in poorer performance."
My idea was that the 91 octane fuel should be just fine, however the engine is knocking quite a bit. I asked a mechanic and he said that I have to use premium 95 or even 98 octane, no matter what the manual says. The manual on the other hand says the use of premium may result in poorer performance.
I'm somehow at a loss now; how could premium fuel result in poorer performance? And what fuel does the Wrangler actually need? Or is it that the fuel in SA doesn't have 91 octane but actually less? Maybe we get ripped off, I'd not be too surprised...
Or maybe the knocking is not normal and something else maybe the culprit? I'd like to stick to the 91 octane fuel, we wouldn't get any premium fuel in the outback anyway. Any advice?
Cheers,
Andreas