What exactly does "slow response" mean?

I replaced my OEM sensors (all 4 ) with bosh units about a year ago after installed a completely new exhaust system. i kept getting codes for O2 sensor malfunction on the rear O2's, and ended up putting the OEM sensors back in. I haven't had a problem since until recently. I had the SES light come on for a few hours, then went off. It came back on and i noticed a slight low RPM stumble in high gear. I went and had it scanned. Came back P0133, ckt slow response, bank 1 sensor 1. I checked the connection to the sensor earlier today when i changed my oil, and it's tight.

The only thing different that was changed recently was new header gaskets due to a motor mount install.

Can i assume that my car just doesn't like bosh sensors?... this seems to be the general concensus when doing a search. I also saw that i should switch the sensors to see if the problem follows the sensor.

In the meantime, is the sensor not reacting fast enough for the computer, or what?

Thanks.

 

The sensor has to respond rapidly to the constant switching from lean to rich and back again. The PCM changes the A/F ratio about 9 times per second, intentionally swinging it back and forth from slightly rich to slightly lean, required for the cats to function. If the sensor responds too slowly, it throws off the A/F ratio, because the PCM is using data that isn't accurate.

The PCM checks the time required for the O2 sensor to switch from lean to rich (or the other way) and if it takes more than 100 milliseconds, the code sets. It only makes this check one per "trip".

The sensors slow down from contamination - lead, silicone, coolant (silicone), etc. When you changed the gaskets, did you use any silicone type sealer?

 

The SES light has turned off, and the stutter has gotten worse, and upon investigation i found a plug wire had gotten too close to a header primary...

as for the header gasket, i'm not sure if there was sealant used, as I had a shop do the motor mounts. I don't believe there was any sealant used, but i'm not 100% sure.

Thanks for the input so far. I'll switch the o2's from one side to the other when i get a chance IF the light comes back on and the code is the same... i'm hoping for a fluke (yea, i'll never get that lucky).