OK a couple days ago got a CEL code came out sensor 1 O2 slow to respond. Replaced O2 sensor, worked find for about 24 hours, CEL went away, about 15 mins afterwards CEL came back on and now when stepping on the gas pedal there is a hesitation followed by a surge of fuel. Called my mech. said could be bunk O2 sensor? Anyone ever had this problem? Known solutions?

 

bunk 02?

 

Bunk = defective like from the factory defective.

Ohh also wanted to mention that when I pulled the OEM sensor off, it was black, and I mean black. I know this means I'm running rich, is there anything I can do to bring it outta rich?

 

go back into the computer & see what code it set ---if its the same --could be defective o2 sensor
if the original sensor was slow you may have been running a little richer--at times

 

Ok this is the 3rd sensor I have gone through where a CEL came up, the code is P0420 Catalyst System Efficiency Below Threshold sensor 1. I'm begining to doubt that it's another defective O2 sensor. I talked to my family mech. and he said a number of things could cause this, MAP sensor problems, throttle position sensor, pinhole leak in exhaust before the sensor, something about vacuum leak. Anyone ever experienced this before? Anyone give any suggestions? My mech. suggested to switch the O2 sensors and see if a CEL pops up reading bank 1 or 2. If it reads bank 1 the O2 sensor is still good, if not its deffective. I'm gonna try this tomorrow but I wanted some ideas from you guys.

Thanks

 

well i would say its not the sensor.

 

Chimera, you have a high-flow cat, don't you? and some other stuff?

 

V2
DC 4-2-1
Magnaflow Hi-flow

Here's the thing though the OEM sensor lasted months before this happened and now with the Bosch sensors, its happening after hours or days. If it keeps up I'm gonna put an O2 simulator on.

And I just put in some Bosch platinum 4 spark plugs (when I put in the 2nd O2 sensor so I know that isn't the problem).

thats it on the exhaust side.

 

but you're getting the code on sensor #1, right? I thought you could only get a simulator for #2. I don't know what "Catalyst System Efficiency Below Threshold" means, but since it's the first sensor that's giving errors, I'm thinking that it isn't a problem with the cat.

Ummm... yeah I have no idea.

 

hmmm maybe you can only get a sim for the after-cat sensor.

Basically what the error means is that the 1st sensor is slow to respond. but I can't see how I could purchase 2 defective O2 sensors in a period of less than 2 weeks. So I'm gonna play around with it and see what errors I get, and then... I dunno I'll figure something out.