: P0153 - HO2S Slow Response Bank 2 Sensor 1

12-12-08, 01:46 PM
Have a 1998 Deville, with 78K miles, at 60K, I had encountered the PO153 code (HO2S Slow Response Bank 2 Sensor 1) had the bank 2 sensor 1 02 sensor replaced with a Bosche.

Then at 70K, another PO153, this time I replaced the same Bank 2 sensor 1 (Bosche).

At 77K, another PO153, cleared the code, then at 77.3, PO153, cleared the code, then at 78K, PO153.

Any advice here?

In advance, thanks . ..

12-12-08, 01:52 PM
Need to add, I had a bad Fuel Pressure Regulator (Great diagnosis from Ranger - many thanks), which was leaking gas into the intake vacuum.

I just replaced it 100 miles ago, and removed the pos bat for 2 hours, to allow the computer to reset the fuel settings.

I am wondering if the leaky FPR was causing problems on my 02 sensor?

12-12-08, 01:58 PM
By your statement, the FPR may have been your problem all along. O2 sensors react to rich and lean mixtures, so a rich condition caused by a raw fuel leak would surely mess up the air/fuel ratios and therefore the "expected" values set into the O2 sensor specs.

12-12-08, 02:41 PM
Your problem might be Bosche. I would have recommended you stick with A/C Delco.

12-12-08, 03:00 PM
Ranger, why do you recommend AC/Delco over Bosche?

I was told the Bosche was OEM replacement . . .

And why do think it might be the BOsche?


12-12-08, 03:57 PM
Many forum members have reported bad results with Bosche stuff.

12-12-08, 05:24 PM
(Robert) Bosch equipment is "OEM style". Original is Delphi or ACDelco. BUT, what company actually made the sensor is the mystery........

12-12-08, 07:29 PM
From what I've heard, most Bosche part do not play well with Northstars.

12-13-08, 06:55 AM
The Bosch sensors are made for multiple applications, while in theory they should work the same no matter what they are in, who knows?
I have seen a lot of Bosch replacements fail, N*'s do not like Bosch plugs for sure.

That code should be an actual sensor malfunction, a specific set of conditions need to be met for that code to set.
The only really important thing to remember is that Bank 2 is the front bank on a N*.
Some people think it is the rear one.

I don't see a lot of Delco part failures on O2 sensors, seems like buying one factory one would be cheaper than buying 3 Bosch parts.