Check Engine light 87 octane?
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Joined: Oct 2013
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2006 C230 Sport
Check Engine light 87 octane?
I just bought a 2006 C230 Sport and it ran fine for 300 miles until I accidentally put about $10 worth of 87 octane gas and the check engine light came on 100 miles later. Should I run through the entire 87 octane left in the tank? Once I do fix the problem, how do I turn off the check engine light? Please help! lol
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Joined: Dec 2006
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From: Toronto, Canada
2019 C300 Wagon; '75 Triumph TR6; previous: 2004 C230 6spd sold after 17 years of driving
87 octane should not cause an issue. I suspect that it had a check engine issue prior to you buying it and they cleared the codes so it was not indicating a problem and after driving for a while the light came back on. Plug in a OBDII and see what codes are stored. I am willing to bet my first born that the seller cleared them so that they could easily sell the car and not have to put money in to solving the real issues with the sensors.
I had a CEL earlier in the year and my scanner indicated an upstream O2 sensor and since the part is expensive here in Canada $576 I wanted to make sure it was the problem and not a random code that got thrown. I cleared the codes and the CEL went away and drove the car for more than 2 weeks and several hundreds of km's before it came back on. I then ordered a new o2 from the US and installed it and the code now has been off ever since
Clearing the codes will usually turn off the light for a period of time but since the issue is still there the light will eventually return.
I run 91 but there has been times when it has not been available at the station and run 87 many times without any issues. You don't get the performance out of the engine and actually get worst mpg so the price spread makes up for the difference. I suspect that Octane is more noticeable on forced induction engines and high performance lumps like the C63. The 2.5L 6 is a bit of a lazy motor and running 87 will probably not make a difference, the laziest of the bunch is what is in the 2.6L in the C240 giving only 168hp
I had a CEL earlier in the year and my scanner indicated an upstream O2 sensor and since the part is expensive here in Canada $576 I wanted to make sure it was the problem and not a random code that got thrown. I cleared the codes and the CEL went away and drove the car for more than 2 weeks and several hundreds of km's before it came back on. I then ordered a new o2 from the US and installed it and the code now has been off ever since
Clearing the codes will usually turn off the light for a period of time but since the issue is still there the light will eventually return.
I run 91 but there has been times when it has not been available at the station and run 87 many times without any issues. You don't get the performance out of the engine and actually get worst mpg so the price spread makes up for the difference. I suspect that Octane is more noticeable on forced induction engines and high performance lumps like the C63. The 2.5L 6 is a bit of a lazy motor and running 87 will probably not make a difference, the laziest of the bunch is what is in the 2.6L in the C240 giving only 168hp
Last edited by Boom vang; Oct 16, 2013 at 09:39 AM.
Thread Starter
Newbie
Joined: Oct 2013
Posts: 14
Likes: 0
2006 C230 Sport
I have actually been a victim of that in the past, sadly. Yet, when that was the case the CEL came on a lot quicker than that. This one took about 4-500 miles? The engine is running fine. I will be taking it Auto Zone after work today. I just thought I would get some input while I'm at work LOL. Thank you, though!
