Question about 1995 Toyota Tacoma

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1995 toyota tacoma 2.7 4cyl/5 manual/4x4 P0420 trouble code

Both o2 sensors were replaced just over a year ago. The cat was replaced less than a year ago because there was a cheater pipe welded in its place. In Feb the check engine light would come on than go out. Eventually it lit up and stays lit. I brought it to a mechanic and he put it on the scanner and told me that I had a P0420. I have a Haynes repair manual and it told me how to check the O2 sensors with a volt/ohm meter. the ohm readings were out of the accepted range of 5-7 ohms on the heated side of the sensors 15 ohms. I also have a chilton's repair manual and it mentions nothing about testing the resistance values but does mention about the voltage values. The voltage varies from .1 to .9 volts constantly changing with both O2s.

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  • wade_olson20 Jun 22, 2009

    Both O2s were replaced at a toyota stealership with toyota parts

  • wade_olson20 Jun 24, 2009

    Both O2 sensors were bad from the start when I bought the truck from the stealership. I was getting 10 mpg. Had them replace them both for $600. Then about a month later the truck died when I came to a light at the left turn where I lived at the time. It took them 9 hours to diagnose my truck and tell me the reluctor wheel had seperated from the crankshaft and crashed into the crank position sensor. They ended up putting in a used engine with 102K. $4600 dollars and counting I am still running into troubles. I am at my wits end. Two weeks after I got my truck back I had a lower ball joint go out at 65mph. This truck has cost me more heartache and money than what it is worth. the last bill for the toe and the ball joint repair was shy of $800. I can not justify sticking a bunch of money frivolously into it. The money I paid into it has exceeded the value. I would like not to give the stealerships another chance to stick it to me. I am now unemployed and living off the unjoyment dole and I don't have the luxury of extras.

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  • Master
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Sensors maybe aftermarket or bad there very sensitive may haft to replace!!!!

Posted on Jun 22, 2009

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