P0204 Code... covered so many times, I know... Just wanted to get your thoughts on live data (video)

Hello all...

I know its been covered a million times, and im just trying to go on the cheap here. Need to get my vehicle inspected and passed by tomorrow so I can renew my plate.

I just wanted to see what you guys interpret the o2 voltage as with the live data I recorded on video link that I have attached ( i dont want to go through the trouble of uploading it on facebook or something...

https://drive.google.com/file/d/1motKLsa_rgJvr8F77SVVXQOAeYODpM2e/view?usp=sharing

Thanks!

 

The video is too short, but based on what I saw, you need a cat converter.

 

When I click link it says file is non-existant. Can you tell us what DTC/s you're getting right now? What codes are currently being thrown?
How many miles on taco and what's the maintenance history? Need some info here

 

Yea, I removed it to make space for a longer video. But I'm currently clearing more space to be able to upload the longer video lol. I was getting the p0204. Ive reset the code. I'll put the link up for the new video in about half an hour. The upstream and downstream o2 sensor differences seem to vary greatly. Even alternating which one is reading the higher V.

its an 2000 with about 256k miles on it. I bought it from the original owner, and he said he really never did anything unless the oil change shop suggested it. Im sure I'm gonna end up putting a new Cat on. Just wanted to see what you guys thought.

 

P0204 means that the ECU detected a fault in the injector or the wiring to the #4 injector. Do you have that code correct?

 

Yea, according to my OBD scanner (unless im dyslexic and it says 0240?). It also gives the top fixes. Which according to this, would be the cat replacement.

Try this link. It says its still processing, so IDK if it will come through or not?

https://drive.google.com/file/d/1motKLsa_rgJvr8F77SVVXQOAeYODpM2e/view?usp=sharing

 

The video is accessible now... Thanks!

 

You're not hearing me man. If that code is correct you put in the message, your cat has nothing to do with it.
P0420 is the DTC the ECU throws if it detects that the catalytic convertor system is not performing correctly.
P0204 couldn't have a suggested fix dealing with the cat as that code indicates the injector problem. Follow me?
Which is the actual code? Throw your scanner on it again before guessing and before I type out a bunch of stuff for a non existant, not needed fix.
If it's P0420 there are still further diagnosing steps unless you just want to guess and throw a cat at it and hope that takes care of it. We just need good accurate detailed info and we got your back

 

Saw the video, the link is working

 

Well, now I'll have to wait to see if it throws the code again lol. I reset it today. It was kinda intermittent and took a while to throw the code last time I reset it after it came on. I found a collapsed vaccuum tube heading into the intake manifold and replaced it. I may not have mistakenly typed the code on here, but, my scanner definitely gave the cat code. Its up to date, and gives the most common fixes. The first one was replacing the cat. Followed somewhere down the line by the "Burn off" procedure??? Im not misfiring, and the truck is running fine. Other than that CEL (which is now reset), i didnt notice any remarkable performance issues.

 

I wasnt quite understanding the correlation of the Voltage reading of the up and down stream O2 sensors in relation to the performance of the cat. Do you know anything about that jazz?

 

The part to ignore is the suggested fixes from the scanners or parts store knuckleheads. And you're asking about the O2 sensor readings which is good as that'll tell you if the cat is working(assuming thee sensors are actually reporting correctly).
Was the video of the system running in open loop? I'm not good enough to tell. Closed loop is when ecu is using default parameters for fuel and air delivery instead of actual readings from the AFR /O2 sensors.

 

Open, or closed loop, i couldn't tell you. I'd assume open, since the code hadn't re-occured yet... i don't trust the guys at the shit parts stores. 98% of the time, i know more than them, and i ain't nothing special. Lol

 

Then the rear O2 sensor didn't appear to be working right. If you were in open loop that is. The rear sensor should signal voltage or not to the ecu, I think. I'll re-watch and reread but I think that's right.

 

I thought open loop was using defaults and closed loop was using sensor information to control trims. Am I mistaken?

 

Oh that sounds right. Mix up in the terminology. Thanks for correcting.

 

the catalytic convertor is an oxygen storage device. When the rear O2 sensor reacts like the front O2 sensor, i.e. not storing O2 / burning/converting, the P0420 code is set.