4eigner
New member
Read the full post.
Please only vote in this poll if you have met ALL 5 of the following criteria:
-Model year 1999
-5FVZE 6 cylinder
-Automatic Transmission
-Under the hood Catalyst sticker states "...CALIFORNIA REGULATIONS APPLICABLE..." in the large box near the middle of the sticker
-THERE ARE/WERE 2 FACTORY INSTALLED CATALYTIC CONVERTERS IN THE EXHAUST SYSTEM
To reduce the variances and improve the accuracy of this poll we're going to only include the specific group noted above.
The purpose of this poll/thread is to determine when Toyota made the switch from a 1-cat to a 2-cat exhaust system in their 1999 model year Cali regulations compliant T4Rs w/ 6cly automatic trans. Let's attempt to pinpoint the month this happened. There's a good chance that the change happened within a calendar month so the last one picked will most likely have vehicles equipped with either system.
To find the month/year your 1999 T4R was produced, look at the driver door jam. You'll see a white rectangular sticker that shows "DATE XX/98" or XX/99 in the upper right hand corner. The XX is actually a number which refers to the month, and the 98 or 99 refers to 1998 or 1999 respectively. If you're voting in the poll, you will be selecting the number that matches the date on your sticker.
In the bottom right corner of this sticker it will show "MADE IN JAPAN" and have "NO.XXX" below it, where XXX is a number which most likely represents the production number for that particular month. We may even narrow it down to a range of numbers if we get enough participants that meet the criteria in this thread.
Part of the reason I created this thread is because of my air/fuel sensor woes. The following sites led me astray from the correct front air/fuel / O2 sensor for the 1-cat Cali emissions 1999 T4R.
Referencing Underdog Racing Development:
URD's chart (Oxygen / AFR Sensors - Underdog Racing Development)
Referencing Denso's website: (Find My Part | DENSO Auto Parts)
Multiple threads on this forum have also netted conflicting (but mostly wrong) information, stating that all Cali emissions Auto 3rd gen T4Rs use the Denso 234-9002 sensor prior to the catalytic converter; this is false. My 1-cat Cali emissions T4R will not accept this sensor. I don't wish for anyone else to waste money by purchasing the wrong & much more expensive sensor like I did.
Now, instead of stating to just buy the 234-9002 sensor if you have 2 cats and 234-4162 if you only have 1 cat, let's expand our knowledge of 3rd gens and find out when the swap happened.
Please only vote in this poll if you have met ALL 5 of the following criteria:
-Model year 1999
-5FVZE 6 cylinder
-Automatic Transmission
-Under the hood Catalyst sticker states "...CALIFORNIA REGULATIONS APPLICABLE..." in the large box near the middle of the sticker
-THERE ARE/WERE 2 FACTORY INSTALLED CATALYTIC CONVERTERS IN THE EXHAUST SYSTEM
To reduce the variances and improve the accuracy of this poll we're going to only include the specific group noted above.
The purpose of this poll/thread is to determine when Toyota made the switch from a 1-cat to a 2-cat exhaust system in their 1999 model year Cali regulations compliant T4Rs w/ 6cly automatic trans. Let's attempt to pinpoint the month this happened. There's a good chance that the change happened within a calendar month so the last one picked will most likely have vehicles equipped with either system.
To find the month/year your 1999 T4R was produced, look at the driver door jam. You'll see a white rectangular sticker that shows "DATE XX/98" or XX/99 in the upper right hand corner. The XX is actually a number which refers to the month, and the 98 or 99 refers to 1998 or 1999 respectively. If you're voting in the poll, you will be selecting the number that matches the date on your sticker.
In the bottom right corner of this sticker it will show "MADE IN JAPAN" and have "NO.XXX" below it, where XXX is a number which most likely represents the production number for that particular month. We may even narrow it down to a range of numbers if we get enough participants that meet the criteria in this thread.
Part of the reason I created this thread is because of my air/fuel sensor woes. The following sites led me astray from the correct front air/fuel / O2 sensor for the 1-cat Cali emissions 1999 T4R.
Referencing Underdog Racing Development:
URD's chart (Oxygen / AFR Sensors - Underdog Racing Development)
Referencing Denso's website: (Find My Part | DENSO Auto Parts)
Multiple threads on this forum have also netted conflicting (but mostly wrong) information, stating that all Cali emissions Auto 3rd gen T4Rs use the Denso 234-9002 sensor prior to the catalytic converter; this is false. My 1-cat Cali emissions T4R will not accept this sensor. I don't wish for anyone else to waste money by purchasing the wrong & much more expensive sensor like I did.
Now, instead of stating to just buy the 234-9002 sensor if you have 2 cats and 234-4162 if you only have 1 cat, let's expand our knowledge of 3rd gens and find out when the swap happened.
Last edited:
. I just wasn't sure if they were on a different assembly line or not. Not knowing if certain configurations received the exhaust changes at different times or not I opted to keep the variables down in an attempt to have a "control group". 
