What happens when you use a wrong fuel type?

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Pacfanweb

Lifer
Jan 2, 2000
13,155
59
91
Originally posted by: Rainsford
Originally posted by: AMDUALY
Nope car should be fine, normally new cars can detect the grade of fuel you put in and adjust the combustion accordingly. Her car will just not perform as good as if she put in premium.

Not that I'm doubting you, but I'm curious how a car can adjust the level of compression in the cylinder.
Doesn't need to, retarding the timing is all it takes.
 

Pacfanweb

Lifer
Jan 2, 2000
13,155
59
91
Originally posted by: MS Dawn
A piezoelectric transducer bonded to the engine block turns the forces from knocking and pre ignition into minuscule voltages that are analyzed by the onboard electronic control unit. If these reach the trigger threshold, the computer will retard the timing until the source stops. This happens on the fly automatically to prevent piston damage. The penalty is with retarded timing, lower engine output when needed under hard acceleration.

I think that's right. :)
That's exactly the way a knock sensor works.
 

Cattlegod

Diamond Member
May 22, 2001
8,687
1
0
Originally posted by: MS Dawn
A piezoelectric transducer bonded to the engine block turns the forces from knocking and pre ignition into minuscule voltages that are analyzed by the onboard electronic control unit. If these reach the trigger threshold, the computer will retard the timing until the source stops. This happens on the fly automatically to prevent piston damage. The penalty is with retarded timing, lower engine output when needed under hard acceleration.

I think that's right. :)

I think that is right as well. However, once the accel picks up that the engine has detonated, the damage has already been done (just not nearly as bad as if the detection wasn't there).
 

Papagayo

Platinum Member
Jul 28, 2003
2,303
23
81
I know that with Acura TSX, they said that the engine will sense the low grade fuel and adjust the engine automatically. The Gas mileage and performance will go down, but will not void warranty..

 

krotchy

Golden Member
Mar 29, 2006
1,942
0
76
My car takes 89, but stupid colorado has 85,87 and 91 Octane only. What the heck kind of car uses 85, a lawnmower? Being from Nevada, I had never seen below 87 until I got here.
 

Scarpozzi

Lifer
Jun 13, 2000
26,391
1,780
126
I'm gonna say though...the RSX is considered a performance machine. Most other cars that size would sport such a low-compression engine that you won't reap any benefits. The computer in that system is the downfall....everything is "too precise" because they're trying to get extra pep out of a smaller engine. In the old days you'd throw a larger V8 in the puppy and increase performance that way. :p