2012 M8 Octane Code

[odi8]

Hi all, my son has a 2012 M8 SP LTD that has been throwing an OCTN code every 15-20 min of riding. Sled had maybe 400mi when we bought it and is now at 800. We've been to the dealership several times to get it figured out and have done or checked the following...to no avail.
Replaced aftermarket can with stock one and replaced all springs;
Swapped out the knock sensor as well as the temp sensor;
Flat land weights put in clutch;
Replaced plugs;
They even tried a new ECU with no luck;
We are now trying to add an octane booster to get the octane up to about 105 to determine if maybe the original owner put a new timing key in it (dealer says they can't tell unless they pull the flywheel etc. off. Next step if that isn't it is seeing if the clutch is out of balance I guess??
My poor kid has over $700 into repairs that have done ####all and is to the point where he HATES this sled and can't wait to rid himself of it. If anybody has any advice or experience with it I'd appreciate it! Thanks much.

 

[mbcat]

Wasn't there ecm re flash available? Try torco accelerator. It actually works not like other oct boost

 

[odi8]

I think that's the stuff we got - torco - comes in about a 2 liter tin jug?

 

[Thunder101]

look for anything that might rattle, cans rattling around can do it but you already switched that out.might not hurt to check coolant level with the front of the sled higher then the rear, check compression to see if its high( maybe its had a head shaved ?
good luck and if you figure it out post your finding.

 

[Sledbrain2]

look for anything that might rattle, cans rattling around can do it but you already switched that out.might not hurt to check coolant level with the front of the sled higher then the rear, check compression to see if its high( maybe its had a head shaved ?
good luck and if you figure it out post your finding.

X2 on checking compression.

 

[arctic2009]

Hi all, my son has a 2012 M8 SP LTD that has been throwing an OCTN code every 15-20 min of riding. Sled had maybe 400mi when we bought it and is now at 800. We've been to the dealership several times to get it figured out and have done or checked the following...to no avail.
Replaced aftermarket can with stock one and replaced all springs;
Swapped out the knock sensor as well as the temp sensor;
Flat land weights put in clutch;
Replaced plugs;
They even tried a new ECU with no luck;
We are now trying to add an octane booster to get the octane up to about 105 to determine if maybe the original owner put a new timing key in it (dealer says they can't tell unless they pull the flywheel etc. off. Next step if that isn't it is seeing if the clutch is out of balance I guess??
My poor kid has over $700 into repairs that have done ####all and is to the point where he HATES this sled and can't wait to rid himself of it. If anybody has any advice or experience with it I'd appreciate it! Thanks much.

Check the fuel pressure. Should be ~45 psi. Check the smart valves in the tank too.

Wouldn't hurt to check the voltage at the pump if the pressure is low. Should be around 14-17 volts.

 

[diggerdown]

Have you had a chance yet to try the higher octane fuel to see it that made a difference?

 

[slyrydr]

things that make the octane light come on....low octane fuel, premium pump fuel is sufficient; old fuel, water in fuel, fuel from station that puts bad fuel in tank; not getting enough fuel into cylinders, low output fuel pump, fuel injectors, plugged filters on smart valves in fuel tank; water in tank, phase separation of ethanol fuel in tank, low fuel in tank, normally happens with less than about 3 gallons; modified head, i.e. shaved head, too much compression, not enough squish; loose detonation sensor, wire broken or shorted; main thing is you're not getting enough fuel into cylinders for the compression you have...lots of little things to look at, probably not injectors, fuel pump, maybe...compression check is easy to do...then i would take the tank off, completely empty it and see what comes out, looking for water in bottom of container you put it in, check filters and lines for plugging, check pump for output.....somewhere in what is listed here will most likely be your problem, good luck..