New spark plugs and carbon buildup.

That’s so stupid: where to you come up with this stuff?

Ok so Toyota engineers thought let’s put a full mark on dipstick and thought hmm.... hopefully no one keeps there oil level there because it will fill the cylinders with oil.
Because we have no idea what we’re doing and need priuschat to fix this one for us.
We will keep our fingers crossed maybe someone cagey over at priuschat will figure this out and let everyone know about how stupid we are.

 

Uh, no. See post #13, with excerpt from Repair Manual.

And for corroboration, from the Owner's Manual:



And from post #13, the Repair Manual lists "dry" fill as 4.3 US quarts.

 

Yeah I've no experience with 2nd gen, only 3rd. I guess it never hurts to hold back about a cup, check level in a day; a lot easier to add oil than delete.

 

"Ad hominem (Latin for "to the person"),[1] short for argumentum ad hominem, typically refers to a fallacious argumentative strategy whereby genuine discussion of the topic at hand is avoided by instead attacking the character, motive, or other attribute of the person making the argument, or persons associated with the argument, rather than attacking the substance of the argument itself." Ad hominem - Wikipedia

Show me a case where keeping oil level above the minimum mark but below the maximum produced excessive engine wear.

 

Which water pump did they change? A North American gen 2 Prius has 4 water pumps.

 

I have a 07 prius 230k miles and i have to change spark plugs every 4 months each time all in carbon build up what can i do?? How to get rid of the carbon inside the engine ??

 

There's an old saying that many problems that look like fueling are actually ignition. Do all the plugs look alike, or are some sootier than others? You're either getting too much gas or too little spark.

If the severity of the problem varies between cylinders, I'd swap coils around to see if the problem moves with the coils. I'd also double-check the plugs to make sure they're correct for the engine. I would also check fuel pressure at the rail (you can often borrow a gauge from Advance or Autozone) to see if it's within spec. If pressure is off spec you may need a new fuel pressure regulator.

 

All spark plugs look the same and also has a strong gas odor Not oil so u can be right i might be getting to much gas will have to check the pressure also the car sometimes gently vibrates when standing on red light and engine does not shut off.