da7

hi Guys, just done some diagnostic on the car, and by scanning the OX1 on the Diagnostic port with a scope, I was getting nothing, and are getting normal readings on the OX2...

I tried scanning the oxygen sensor at the front exhaust manifold and the reading is normal, and at the same time the signal disappears from OX2, so leads me to the conclusion that OX2 is the one at the front and OX1 is the one at the firewall.... Is that right?


So my main question is, I noticed the front sensor has only 1 wire, but the sensors that are sold on ebay and other car parts stores are 4 wires, does any body know if the one at the firewall, what part number should it be? And whether it's a 4 wire oxygen sensor? Or single wire? Appreciate any help, thank you...

ASG14

iTrader: (1)

1 wire sensor???? It's supposed to be a 4 wire.

B1S1 is firewall, and B2S1 is Radiator side,

da7

I think it's because over here in 1994, the ES300 is still OBD1 and uses 2 oxygen sensor instead of the 3 oxygen sensor in california and we also don't have the post-cat oxygen sensor... so do you have any idea what you guys use prior to that? Maybe like 1992-1993 model with the 3vz engine?

ASG14

iTrader: (1)

^ No, 1994 ES300 is OBD1, same as the Camry.

da7

so any idea which one is the OX1 and which one is OX2 as pinned out in the diagnostic port? and the part number for the 1 wire oxygen sensor? the only one i see on ebay is this http://www.ebay.com.au/itm/TOYOTA-CA...ht_2156wt_1159

ASG14

iTrader: (1)

Dude, YOUR 1MZ-FE DOES NOT USE A FREAKIN 1 WIRE SENSOR! Thge 92-93 3VZ-FE DOES!


PM me your VIN number and I'll get back to you right away with EXACTLY what it is so you know. Cause at this point, I am thinking you have a 93 ES300 and NOT a 94.

dontmachme

if you have a one wire o2 sensor and its a 94 its was built in 93 as a late 93 and titled as a 94. does your timing belt cover say 3vz fe and have cap and rotor ignition not coil pack? if its 3vz and distributor ignition than you have a 1 wire o2 sensors. and you can get universal 1 wire o2 sensor at oreileys auto parts for like 34 bucks

da7

ya, it's a 94 probably built late 93 or what ever, but it's a 3VZ definately not 1MZ and it's 1 wire o2 sensor, that's what i'm getting at regarding that it's the model with 2x single wire oxygen sensor in my second post, not sure what the confusion was, but i'm trying to see who makes one that is direct plug in replacement with a part number that i can look up rather than the universal sensor where I have to splice the wire, and the second question was that which sensor is OX1 and which is OX2 as connected to the diagnostic port?

dontmachme

when i did them on my 93 ox1 if i remember right was the front o2 sen but it was the one by the fire wall you have to place the engine as if it was rear wheeldrive in your mind not inverse like it actually is if that makes any sense. so ox2 would be near the cooling fan. and im not sure where you live cause region effects price but i work at autozone and i know that we sell a direct fit plug and play bosch o2 sensor for like 65. but thats in indiana. but if you go to autozone .com and put in part number 12112 that will pull up a flange mounted one wire direct fit o2 sens that fits front or back. my reconmendation would be to change both of them at the same time. i change only one on mine and a week later the other one had a engine light for it. just my luck lol. but changing them both would be a good decision.

ASG14

iTrader: (1)

your car is not a 1994 car! It's a 1993!!!!!!!!!!!!!!!!!

DrBlack

word. He speaks the truth