This will help your cars performance

drain fuel tank ,change fuel filter &add clean gasoline when it start will smoke for awhile

Hello, If the D is for diesel, then you will have to siphon to fuel out of the tank until you make the fuel tank light enough to drop the tank. Then remove the tank, turn it upside down after removing the fuel pump. The gasoline that is in the tank by mistake at best could be used in a 2 cycle engine. For the most part it is junk fuel. Otherwise it can be used to start fires or clean tools.

Add a small amount of diesel to the tank and swish it around and dump that fuel as waste. Then try to immerse the fuelpump(if in tank) in diesel fuel to get out the lighter more explosive gasoline. Try blowing out the fuel that has reached the motor and have the fuel filters changed. When everything is together add only several gallons to prime the system before trying to start it.

If you suspect gasoline is in the injectors, they may have to be removed and cleaned too.

Now if you added Diesel to a car using gasoline, then it can be a little easier to fix. You can use the fuel pump in the tank to drain the tank via the fuel line coupler at the fuel filter. Remove the filter and turn on the key with a rubber line connected to the tank side of the fuel line. The fuel pump will drain the tank. It would be good to remove and clean the tank, but not necessary. The residual Diesel fuel will dilute over time.

If either fuel is mixed together there will be vapors. Ventilate and put down a rubber mat or blanket under the catch bucket to insulate it from sparks and static.

I hope my solution is very helpful to you. I want to add that sometimes Comprehensive car insurance may pay for this service. You should call your Insurance company and see if your insurance covers this.

it all depends on how much diesel remained in the tank before the gasoline was added, and how new and sophisticated the diesel engine is. In a 2007 or newer clean diesel engine, any amount of gasoline will probably damage the sensitive emissions control components (DPF, OxyCat and SCR) and system. In older engines with much less sophisticated and "touchy" emissions systems, a lightly diluted (say 90 percent diesel/10 percent gasoline) mix would probably pass through with little or no detriment. It might simply cause reduced engine power, perhaps a bit more noise, and possibly a sharp warning from the emissions sensors that detect something other than pure diesel exhaust. It's high concentrations of gasoline that spell real trouble. Whether a modern clean CRD diesel or an old indirect injection unit, burning straight gasoline or highly diluted diesel fuel will almost certainly result in catastrophic damage to the mighty diesel engine.

well this oil is going some were and my gess is its burning it just becouse you have still got full power,,, or at least you think you have!
after all has it been on a rolling road to find out just how much power it realy has????? i would not be to botherd if it uses say half a pint a month,,,even if it used 3 pints a month you would hardly see any blue smoke just drive it,

The first thing i'd tell you is to not run the engine at all before fixing this if possible. Diesel fuel doesn't burn very good in a gasoline engine, if at all... There is not enough compression in a gas engine to get the diesel hot enough to burn, even with a spark plug.

There is a few ways to go about this but the easiest one is to find and disconnect the line coming from the gas tank to the engine, as close to the fuel pump as possible (preferably before the filter) and route it to an empty container, then jump 12V to the fuel pump motor terminals, or jump the fuel pump relay terminals (to get the pump running) and let it pump the diesel fuel out in the container...

As a precaution I'd change the fuel filter after this, fill the tank back up with clean gasoline, and give the car a good run... You can expect the engine to smoke and run bad for a little while, as there will still be a little diesel going through.

As for the cost to get it done, I really couldn't give you a straight answer... They could do it like I said or another way (drop the gas tank...) It's not that hard to do if you do it yourself or find someone you know who can do it or a good "backyard" mechanic, but I'm sure some of the shops out there could write up a nice repair bill for this...