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Toyota Repair/98 toy.rav4,


QUESTION: have a 98 rav4 with 125000mils,has a auto trans.fouls the plugs,take in to get repaired only to have them do a tune up and change plugs,works fine about 50 miles or so than starts looseing power and fuel milage drops to like 5mpg. what could be fouling the plugs like that.

ANSWER: Does the check engine light turn on while driving?
Is there any smoke from the exhaust?

---------- FOLLOW-UP ----------

QUESTION: no noticable smoke and no check engine light,

Spark plugs usually get fouled by either too much oil bypassing the piston rings or too much fuel, incase of oil fouling the deposits will look black and wet, in case of of too much fuel the deposits will be black but dry, please let me know which you think is the case.  

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Ted Ritter


I have more than 28 years experience as toyota technician, I will be able to answer most questions related to the Toyota product line up to the present year models,I am located in the US but welcome questions from other regions of the world. When asking a question please provide specific information: year,model, engine,transmission information. Provide as much information as possible including a brief repair history if possible. I have been a volunteer here for more ten years an have answered over 16,000 questions helping Toyota owners with their problems and save thousands of dollars without any compensation, some of my answers are published on many other websites including google and various automotive forums. DONATIONS ARE VERY MUCH APPRECIATED, IF YOU HAVE RECIEVED HELPFUL INFORMATION PLEASE MAKE A DONATION. AS OF TODAY (JULY 22, 2014) ALL REQUESTED GRAPHICS, ILLUSTRATIONS, DIAGRAMS, PHOTOS, WILL REQUIRE THE MINUMUM DONATION UP FRONT.


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