Question about 1994 Toyota Pickup

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Code 25- Lean Air-Fuel Mixture

1994 Toyota 4x4 X-Cab SR5 with 214,000 miles. I take quite good care of my vehicle and it shows. Brought vehicle to Toyota dealer in Runnemede, NJ. Technician discovers that the large intake tube connected to the throttle body is cracked and causing a vacuum leak downstream of the MAS. Installed myself, code cleared. A couple days later the code returns. Back to the dealer and the Service Manager tells me that I need 1) new injectors, and 2) new spark plugs. I question him directly as to why I suddenly have (6) injectors which has somehow simultaneously all gone to **** and the spark plugs (Bosch Platinum) has suddenly stopped working? Slightly changes his tune and tells me now that they are "clogged" and the plugs aren't "hot enough." Cost to replace injectors was quoted at $1050 for just the parts. Didn't bother any more from there. Paid for the diagnosis and left.

Having a college background in chemistry and being the son of a 40+ year mechanic, I headed over to AutoZone and picked up (4) cans of Berryman Chem Tool Fuel injection cleaner, (2) cans of Gumout, and (2) cans of SeaFoam. Dumped the (4) cans of Berryman into the fuel tank. Ran the truck and emptied (2) cans of Gumout into the throttle body, and thew the remaining (2) cans of SeaFoam into the tank before filling it back up. Drove around the local highway, up and down [repeatedly] on the throttle get the solvents working.

Now, my feeling is that I was being ripped off by the suggestions made by the dealership. The plugs have been in the vehicle for 6 months without any problems. I also add fuel injection cleaner to the fuel at least a couple of times per year (mininum). I am also not sold on the idea that the NGK or Denso plugs are any better than the Bosch, as I have used them in other vehicles with absolutely no problems whatsoever.

Please advise. Thanks.


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  • 2 more comments 
  • thediscusthr Feb 10, 2009

    Can you give me the Denso plug number?

  • thediscusthr Feb 10, 2009


    Can you supply me with the part # for the Denso plugs?


  • thediscusthr Feb 10, 2009

    I guess I'll give the plugs a shot. See how it goes. I would have gone with the spark plug replacement had he not tried to rip me off with the injector replacement.


  • thediscusthr Feb 10, 2009

    Will do. Do you recommend that I purchase from the Toyota dealer?




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Here is the real scoop form a real Toyota Service Manager, who is NOT interested in ripping you off or steering you wrong:

I take Bosch plugs out of engines quite regularly. Guys come in, with all kinds of lean codes, and I tell them that the plugs are incorrect. They are, in fact, not correct for your engine. I take out the Bosch/Splitfires/whatever, and put in the right Denso plugs, and everything is copacetic. Believe it or not, the engine IS designed with a specific Denso plug. Regarding the injectors, he is indeed ripping you off. Replacing 6 injectors for a code 25 is BS.

Please respond back if you have any other questions.

Posted on Feb 10, 2009

  • 1 more comment 
  • Toyota Ed Feb 10, 2009

    The 1994 V6 (3VZE) takes K16R-U plugs.

  • Toyota Ed Feb 10, 2009

    If you are going to replace the plugs, you might as well replace the wires too, if they ar 5 years or older.

    5 years is the life-expectancy of wires.

  • Toyota Ed Feb 10, 2009

    Yes. Toyota dealer is the best route.



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