Prior to me buying my car on eBay, someone put regular gas in it. So now I have this car with half a tank of regular gas. The car only takes premium. The poor car is shuddering and idling funny. Should I:
Wait till all the gas is gone to add premium?
Fill the rest of the tank with premium?
Add an octane booster?
I don't want to burn the catalytic converter.
Thanks, mwah!
2006-12-01 06:29:23 · 13 answers · asked by french7suzi 2 in Cars & Transportation ➔ Car Makes ➔ Mercedes-Benz
On the 560SL Idling rough is from the carbon build up in the throttle body and heads and the heavy detergent low octane fuel mixing together.... Easy fix with no repairs needed...
Depending how far away your parts store is stop and put 3 to 4 gal 92 or 93 Octane in the tank (super)
Go to your local parts store Look for (might call 1st)
Techtron made by Chevron ...buy 2 bottles...
Go to Gas station put one Bottle in and top tank off..
Check oil level make sure its full.
Drive normally as you would every day...
when you get down to below half a tank fill back up and Drive
When it gets back down to a 1/4 of a tank
Put in the other bottle and drive as normal...
Before now you should notice a difference...
If you decide to use just Octane Booster it will just ad to the Octance, not clean the sysytem as needed... I recommend Octane Booster after your done cleaning the system out only...
After that tank full change oil and filter is highly recommend...
Side notes If the car has over 25000 miles the fuel filter is recommend replaced at 30000.. I change mine every 15000 to 20000 ... Also you might not know it but your Injection system is high pressure so when you fill up and the nozzle clicks just round it off to the nearest nickel.. If you stand there like some people do and fill it til it over flows, click ,click, click that blocks the return fuel line coming back from the engine for the 1st 1/4 of gallon and causes bad fuel mileage and problems with idling when cold.... Just thought you would like to know...
Will be a fun car.....
2006-12-01 07:00:38 · answer #1 · answered by Spinner...428 6 · 2⤊ 0⤋
If the car is not running well its likely not the gas. It's ok to mix octanee when it come to fuel (How do you think they get the 89 Octane when they only have 87 and 92 octan tanks in the ground? put in some injector cleaner and an octane boost with a fresh tank of gas (get a Good quality gas too. Not from your local convince store) and see how it runs. If it runs better then the problem is solved. If it still runs bad you would need to replace the plugs and wires on it. I would also take the time to change out the fuel filter. Hope this helps.
2006-12-01 06:41:45 · answer #2 · answered by gearnofear 6 · 0⤊ 0⤋
D. Drain the tank.
Or, if that's not an option, add the booster, then fill with premium, cross your fingers.
Typically, requiring premium is a compression issue, not a catalytic converter issue. As such, your car would be fine once all that nasty blue-collar gas is gone. The low-brau fuel is igniting too soon and burning too quickly, but is not burning incompletely and over taxing the catalytic converter.
If someone has put in genuine 'Regular' (as in circa 1979 regular-with-lead, not 'regular unleaded' as I hope you mean) catalytic converter destruction would be accomplished within a few miles.
2006-12-03 08:38:38 · answer #3 · answered by John W 2 · 0⤊ 0⤋
You won't hurt the cat unless you do something really stupid like put diesel in it. The cat doesn't know or care what the octane rating is.
Add a can or two of octane booster and fill it up with premium. You should be fine. Or just fill it up with 93 octane if it's available locally.
The engine management system SHOULD protect you from serious damage, but as you have learned it runs like a PIG on regular. Drive it GENTLY for the first few miles after filling it up.
2006-12-02 07:37:04 · answer #4 · answered by Bostonian In MO 7 · 0⤊ 0⤋
Fill the rest of the tank with premium and add an octane booster.
If the problem don't clear up in about 5 minutes of driving, you have some other problem.
2006-12-01 06:46:10 · answer #5 · answered by eferrell01 7 · 0⤊ 0⤋
The problems you describe are not from low octane fuel. That car has a valve on the side of the fuel distributor that regulates idle called an EHA valve. That would be more likely to be bad than low octane fuel. That car also has several vacuum hoses that can crack and cause the problems listed. Take it to a MB independent shop and have them check it out.
2006-12-01 16:40:10 · answer #6 · answered by uthockey32 6 · 0⤊ 0⤋
You bought the car with a conditon of shuddering and idling funny,You or the person who sold the car say the "regular" gas is causing these problems. This thought could be wishful-thinking, maybe the "car" has driveability issues! When purchasing a Mercedes "used-car",an exp. Mercedes tech should do a "Pre-purchase" inspection to confirm the condition of all systems of the vehicle being bought. It's not to late,please have a "pro" ,inspect the car ,protect your investment. Good luck!
2006-12-01 14:32:03 · answer #7 · answered by Hank 4 · 1⤊ 0⤋
I would add the octane booster and fill remainder with premium. It should be fine. After the next two fill ups with pure premium if there's still problems, consult with a Mercedes-Benz mechanic.
2006-12-01 06:40:05 · answer #8 · answered by eehco 6 · 0⤊ 0⤋
Fill it with the premium, it should dilute out enough that you should wind up with a decent mid-grade mix. If it still goes funny onlyadd about 1/4 - 1/2 bottle of booster. Too much and you might crisp the valves.
2006-12-01 06:33:46 · answer #9 · answered by tkrwlly 3 · 0⤊ 0⤋
First, why did you gamble on this purchase? Maybe it was a real good deal. STILL...........
Fill it up with premium, drive gently for a while, and stop worrying. It will be fine, assuming the gas is the problem.
2006-12-01 06:39:28 · answer #10 · answered by Trump 2020 7 · 0⤊ 0⤋