05 C240 CEL on
#1
05 C240 CEL on
I over filled gas and spilled a bit the other day, and then the day after CEL came on. Is this what caused to CEL come on? If so how to fix this?
I don't see anything else could go wrong so sudden.
Any clue guys?
And is OK to use reg 87 on C240?
I don't see anything else could go wrong so sudden.
Any clue guys?
And is OK to use reg 87 on C240?
#2
Super Moderator
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If you overfill these cars it saturates the charcoal canister in the EECS (evaporative emissions control system) This will trigger a CEL. Once you have run the car for a while & reduced the fuel level, the EECS is vented into the engine intake system & burnt off. The charcoal canister dries out & the CEL will go off.
Do not top off the tank.
Do not top off the tank.
#4
MBWorld Fanatic!
I am only asking the following to better understand...
What damage can occur if we use 87 Octane gasoline? If I understand correctly, high compression engines require high octane gasoline and if we use regular gasoline, the knock sensor will sense the knocking and retard the timing slightly. As a result, the mileage/performance will suffer. How does using 87 gas damage any component?
For the record, I use 93 Octane gas in my '07 C280 and 91 Octane gas in my '04 C320 because that is what is secified in the respective owner's manuals.
What damage can occur if we use 87 Octane gasoline? If I understand correctly, high compression engines require high octane gasoline and if we use regular gasoline, the knock sensor will sense the knocking and retard the timing slightly. As a result, the mileage/performance will suffer. How does using 87 gas damage any component?
For the record, I use 93 Octane gas in my '07 C280 and 91 Octane gas in my '04 C320 because that is what is secified in the respective owner's manuals.
#5
Super Moderator
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87 AKI fuel (anti knock index fuel as stated on US pumps only - ROW states RON = Research Octane Number) will not damage the engine in any way unless it's rubbish & the knock sensor can't retard the timing sufficiently to stop knock, pinging, pre ignition, detonation - whatever name you know it by. Knock can be very destructive.
The problem with 87 octane is that the car will run with it's timing permanently retarded which is no good for consumption or performance. These cars have very conservative engine mapping standard but I recommend running on high octane fuel for best performance & gas mileage.
The problem with 87 octane is that the car will run with it's timing permanently retarded which is no good for consumption or performance. These cars have very conservative engine mapping standard but I recommend running on high octane fuel for best performance & gas mileage.