02 sensor

[bigbodychevrolet]

I'm still getting a po420 after new rear cat. I'm thinking 02 sensor one or both of them. have no way to check them. anyone know where i can find a wiring diagram. like which wires are for the heater circuit in order to check the ohms? thanks

[Gregtrd]

I'm still getting a po420 after new rear cat. I'm thinking 02 sensor one or both of them. have no way to check them. anyone know where i can find a wiring diagram. like which wires are for the heater circuit in order to check the ohms? thanks

just clean them with carburator cleaner and slap them back on.

[hskrsolara]

I'm still getting a po420 after new rear cat. I'm thinking 02 sensor one or both of them. have no way to check them. anyone know where i can find a wiring diagram. like which wires are for the heater circuit in order to check the ohms? thanks

just clean them with carburator cleaner and slap them back on.

but remember to be EXTREMELY careful when doing this cause the wire in the sensor is very sensitive and will break/move easily. Use a qtip with the cleaner, but be very careful.

[Gregtrd]

I'm still getting a po420 after new rear cat. I'm thinking 02 sensor one or both of them. have no way to check them. anyone know where i can find a wiring diagram. like which wires are for the heater circuit in order to check the ohms? thanks

just clean them with carburator cleaner and slap them back on.

but remember to be EXTREMELY careful when doing this cause the wire in the sensor is very sensitive and will break/move easily. Use a qtip with the cleaner, but be very careful.

sounds like youre talking about the mass air flow sensor, i
thought that he was talking about o2 sensor/ air fuel sensors.

[hskrsolara]

ah shoot, I misread the title. lol, well I guess he can clean his MAF too now!

The 02 sensors are much easier to clean.

[Midias]

Do NOT clean the MAF with carb cleaner it can leave behind a residue that can mess with the sensor and some carb cleaners can melt the plastic. Just USE MAF cleaner CRC makes it and it is in almost every autoparts store.

[bigbodychevrolet]

thanks i don't think i have a MAF its an 01 5SFE think i just have the IAC, i've tried cleaning the precat one. that leads to a second question. where is the plug for the post cat sensor? under seat? center console? thanks

[Midias]

If I had to take a guess on plug location it would be under the car behind the rubber stopper the wire goes into. Just follow the wire from the O2 sensor it should be close. If cleaning it does not work try the anti fowler method.


here is a mechanical solution
ou will need a set of Spark Plug Anti-Foul's they are 18mm HELP! brand Part#42002 or 42009.



You will need to drill out a 1/2" hole in one of the Anti-Foul's


Unbolt your 2nd O2 sensor *NOT THE ONE ON THE HEADER, THE ONE ON THE Y PIPE BEHIND THE CAT*
(I would spray a little WD40 on this o2 as well before removing)



Now screw on the Anti-Foul with the 1/2" hole on top of the regular one and then screw it into the hole for the 02.



Screw the 02 into the Anti-Fouler's tighten everything up, Then disconnect the (-) Battery terminal for about 1 minute.

[bigbodychevrolet]

thanks for everyones help. I just cant find the connector to unplug the rear 02 sensor in order to get it out to clean it or put the antifouler in. It goes into the body and has a rubber boot sealing it. i've had the center console out and looked under both seats the only wires i saw were to the seat belt warning lights nothing like an 02 sensor plug. are you saying i need to just pull the crap out of it until it comes out?

[Midias]

The connector is under the car just keep pulling it out till you find it from under the car.

[agent007]

move the driver seat all the way foward and look under the seat. it plugs in by/under the carpeting. atleast thats where mine was on my 1mz when i changed mine.

[bigbodychevrolet]

i would of found it when i first looked, but i didn't look under the carpet. i had to take the drivers seat out and center console to get to it. I cleaned it with brake parts cleaner its not supposed to leave a residue. it was pretty dirty...still looking for any info on which terminals are for voltage checks and which are for heater circuit check thanks. may end up just replacing both and the three way cat also. i assume the 02 sensors are original. i have 135k i hear they get sluggish with that age and can throw a code. It doesn't look like i'd have any room to do the antifouler mod. as of right now the end of the sensor is about half an inch away from the body. anyone else run into that? any help will be appreciated thanks everybody

[aleki2424]

ah shoot, I misread the title. lol, well I guess he can clean his MAF too now!

The 02 sensors are much easier to clean.

didnt know u can clean 02 sensors

[bigbodychevrolet]

You can clean anything thats dirty....

[Gregtrd]

If I had to take a guess on plug location it would be under the car behind the rubber stopper the wire goes into. Just follow the wire from the O2 sensor it should be close. If cleaning it does not work try the anti fowler method.


here is a mechanical solution
ou will need a set of Spark Plug Anti-Foul's they are 18mm HELP! brand Part#42002 or 42009.



You will need to drill out a 1/2" hole in one of the Anti-Foul's


Unbolt your 2nd O2 sensor *NOT THE ONE ON THE HEADER, THE ONE ON THE Y PIPE BEHIND THE CAT*
(I would spray a little WD40 on this o2 as well before removing)



Now screw on the Anti-Foul with the 1/2" hole on top of the regular one and then screw it into the hole for the 02.



Screw the 02 into the Anti-Fouler's tighten everything up, Then disconnect the (-) Battery terminal for about 1 minute.

if you want to erase the cel just remove the (15amp EFI fuse) in the engine bay fuse box for 30 seconds, its easier.