Hi Guys,

In your experience does the primum fuel lowers mpg? I got 20.2 mpg all city dvng with my 4 cylinder( 2004) and 91 octane fuel.

Cheers,

Use what your manual recommends. 91 octane isn't gonna yield any gains or benefits. Just because it's a "higher octane" doesn't mean it's a better type of fuel.

It's all based on your engines compression ratio. The V6, even though the manual says regular, it can also run with premium which has been dyno proven. But it's not worth the extra money.

well Thanks,

Manual says minimum 86 octane will be fine but I put 91 cause it has better cleaning agent ( Petro Canada gas station). I just bought this car and that was my first filling up.

20.2 mpg seems kind of low for even all city driving and I was wondering that 91 Octane gas is the culprit.


I

just use regular or 87 octane

If you run premium you need to bump the timing. Premium fuel burns at a slower rate then regular. So you need to bump the timing to allow the engine more time to burn the fuel more efficently. If you dont you will have unburnt fuel leaving deposits on your valves.

I could have sworn that I read posts in the past by some people who claimed that the Accord V6 will detect if higher octane gas has been put in (by detecting the octane?) and the ECU will adjust the spark ignition timing accordingly and automatically?

I put 91 octane in my Accord V6 for two weeks just to try it out to see if more power resulted, but I couldn't tell. I figured given the if-fy transmission, I didn't want to put more torque through the transmission anyway :)

If you run premium you need to bump the timing. Premium fuel burns at a slower rate then regular. So you need to bump the timing to allow the engine more time to burn the fuel more efficently. If you dont you will have unburnt fuel leaving deposits on your valves.

The ECU would no doubt handle timing control.

If you have a V6, 93 octane+ is worth it if you like performance. Also, the V6 will ping on regular fuel in some places.

yes that's true. accordlover is correct. it has also been dyno-proven. the accord baselined at 195whp and 175wtq. as far as i can remember it gained about 10whp and i forgot the wtq. it's not worth the money unless u actually use that power.

So, I switched to 87 octane fuel, changed Air filter, cleaned throtle body and checked the spark plugs fine, but my MPG has barely improved.

All-city driving is still giving me around 20MPG on my I4.

This is about the milage I used to get on my previous car which was a V6.

Please advice what else could be done.

Thank you all.:nuts:

Good lord almighty... another fuel-economy/gas-choice thread! :D

Ward should tax these new threads, he'd retire early.

Oh, on-topic... use les' searches, merci becoup! ;)

So, I switched to 87 octane fuel, changed Air filter, cleaned throtle body and checked the spark plugs fine, but my MPG has barely improved.

All-city driving is still giving me around 20MPG on my I4.

This is about the milage I used to get on my previous car which was a V6.

Please advice what else could be done.

Thank you all.:nuts:

When I tried 89 octane my MPG also tanked @20mpg in town. Going back to 87 yielded this: Since I fill up at 1/2 tank the first fill was a mixture of 89 & 87......20.5 mpg.

The second tank of 87 was 22.4, the third (all 87 no mix) was back to 25mpg as it has been for years. Cured me! 87 octane it is. This was the 4 banger five speed stick.

The ECU would no doubt handle timing control.

If you have a V6, 93 octane+ is worth it if you like performance. Also, the V6 will ping on regular fuel in some places.

Unfortunitly I dont, so if it adjust the timing with premium will the computer adjust the fuel rate with a cai?

How do you adjust the timing since it is computer controlled?

With a tuner or on a scope.