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What O2 sensor to buy for Cali truck with only one cat
I recently bought a 1999 Tacoma that was originally bought in California. The emissions sticker confirms and reads "...confirms to ... California regulations applicable to 1999 model year"
However, underneath there is only one catalytic converter which then transitions to a newish looking exhaust pipe containing the downstream O2 sensor. I am thinking someone deleted the 2nd cat due to rust.
I pulled the codes today after getting a CEL and it only shows P0133 which is bank 1 sensor 1.
From what I have read on California trucks the first sensor is A/F. Denso only lists 1 sensor for automatic 4wd which is 234-4162 and fits both upstream and downstream. Denso doesn't list A/F sensor and neither do the toyota parts sites.
I think this is true from more google searching: only 4Runners have different upstream/downstream sensors for the 1999 California years. My 1999 California Tacoma has the same O2 sensor upstream and downstream so I need the 234-4162.
I live in Canada and my truck says it conforms with California Regulations Applicable to 1999,.. Only 1 Cat with upstream A/F sensor and down stream 02 sensor to let me know my Cat is functioning properly. I find it hard to believe Japan built a different Catalyst OBDII system and ECU just for California, but then again it is California test pilot for EPA standards.
There is no room on a Crossover pipe for a cat if it travels over the top of the bellhousing like most USDM Toyotas with the 5vz-Fe, AFAIK only JDM diesels have a crossover pipe under the tranny, like all new Tacoma's 2005+ which really sucks due to clearance issues for offroading.
I live in Canada and my truck says it conforms with California Regulations Applicable to 1999,.. Only 1 Cat with upstream A/F sensor and down stream 02 sensor to let me know my Cat is functioning properly. I find it hard to believe Japan built a different Catalyst OBDII system and ECU just for California, but then again it is California test pilot for EPA standards.
There is no room on a Crossover pipe for a cat if it travels over the top of the bellhousing like most USDM Toyotas with the 5vz-Fe, AFAIK only JDM diesels have a crossover pipe under the tranny, like all new Tacoma's 2005+ which really sucks due to clearance issues for offroading.
I hate to tell you but you have a standard 49-state (& Canada) 1999 truck with two O2 sensors and no A/F sensor. The truck meets Cali regs to be used in California but could not be sold new in California in 1999--or several other states that adopted the same standard in 1999, including my own New Jersey.
The giveaway is the HO2S(2), TWC in the line below Engine Family in the upper left corner. This means two heated oxygen sensors and one three-way cat--and NO A/F sensor. A true Cali will say A/F S, TWC(2), HO2S for Air/Fuel Sensor, two three-way cats, and one heated oxygen sensors. Also, the bottom line should say: "CAL & OTC" not "FED & CANADA" See attached for a 1999 Cali and you will see the missing language allowing the truck to be sold new in California:
To the OP, I am not that familiar with Tacos, but no 4Runner 5VZ-FE's were built with A/F sensors and one cat. I suggest you check that line in your underhood label to see exactly how your truck was built, and if it says HO2S(2) you need an O2 sensor up front. If it says A/F, you need an air/fuel sensor. The wrong sensor will not even plug up, as the A/F plugs are different.
Many thanks. Mine was bought new with 85 miles in late 1999 (built in March) in California but the sticker matches above... meaning it has 1 cat and only O2 sensors. Many, many thanks for your help. Would have never decoded that on my own!
Something funny there. Late 1999? They went into MY 2000 in July of 1999. I bought my March-built 1999 in late May as they were clearing inventory for the incoming new model year. I bet the Cali sale with 85 miles was in fact a resale of a truck sold as new in some other state. Then the owner died or something weird and it never got driven.
Good to know, interesting they ask $260 A/F/02 sensor at Toyota, and the rear an 02 for $150 and all this time they are slightly different types of 02's that do the same thing with extreme price difference, sounds fishy. I was pointing out that all vehicles say "Conform with California"
Good to know, interesting they ask $260 A/F/02 sensor at Toyota, and the rear an 02 for $150 and all this time they are slightly different types of 02's that do the same thing with extreme price difference, sounds fishy. I was pointing out that all vehicles say "Conform with California"
First, don't pay dealer price. Get OEM Densos on Amazon or rockauto for the exact same sensor without the red box. Second, wideband A/F sensors and traditional O2s are very different technologies and produce a very different kind of signal. They are probably worth a premium, just not what the stealers charge.
And again, your truck does not use an A/F sensor. It uses O2s front and back.
I understand, again, thanks for clearing that up but they are not the same part, and I don't shop at the dealer, I have wideband for my Eclipse and the fake A/f/O2 connected to the fake A/f ratio gauge similar to the upstream 02 we run.
04-19-2016, 04:38 PM
