ncsurveyor2007

I'm getting codes 1133 and 1153 which are o2 sensors. How many are there and how do I know which ones to replace?

m6 c5

There are four total o2 sensors on the car, the two you are getting codes for are the front two.

madmatt9471

P1133 Heated Oxygen Sensor (HO2S) Insufficient Switching Bank 1 Sensor 1
P1153 Heated Oxygen Sensor (HO2S) Insufficient Switching Bank 2 Sensor 1

These are your two FRONT O2 sensors - Part Number - AcDelco AFS 75 - GM# 19178930

I was fouling out the Passenger side "ONLY" on mine and the Original AC Delco AFS 75 (GM 19178930) were still in there with 100,000+ miles on the O2 Sensors themselves -

Realize that you can even have one go bad without receiving a O2 sensor code!!! (I and others have had this happen)

Plus they have 735 RWHP Supercharged miles with Methanol Injection on them too!

I just put in the 2 new Front AC Delco AFS 75(GM 19178930) these are a New and Improved design as well, instead of slices in the sensor tip they have holes around it instead) -

Pictures:

New Style O2 Sensors AcDelco -





Old Sensors (AcDelco AFS 75) Passenger Side on RIGHT in Picture (100,000+ Miles on the Original O2 Sensors)







Thanks,Matt

ncsurveyor2007

Thanks guys. My 99 has LG long tube headers which were installed before i bought the car. I'm assuming the o2 sensors are still the same though? I'm ignorant when it comes to this stuff, sorry.

madmatt9471

No problem -

How many miles on the Vette (O2 sensors)?

Make sure you also check all the wiring to make sure the wires are not melted anywhere - they are easy to see when you are under there.

Thanks,Matt

ncsurveyor2007

110,000 miles. Not sure if they've ever been changed but I'd imagine they have since I've got headers and cam

ncsurveyor2007

Are the sensors pretty easy to get to once I'm under the car?

madmatt9471

Yes! It is time to replace those - get some soon! They are toast

I got mine from Amazon for $32 each with free shipping ($64 for both, free super saving shipping)

Thanks,Matt

madmatt9471

Yes! Easy and straight forward -

Thanks,Matt

madmatt9471

Not! Usually people overlook these as I did -

My bet is that they were never replaced and they are the original ones from the factory and that is why you got the issues!

Thanks,Matt

m6 c5

You probably are running rear O2 sensors with adapters to allow them to plug into the front O2 sensor harness so you will probably want to get two new rear O2 sensors. The reason they use rear O2 sensors is because they have stronger heaters in them which is needed because they are placed further back than stock.

madmatt9471

This is debatable - They have been tested and show no difference

Make sure you inspect them first before you get anything

Thanks,Matt

m6 c5

Ah well either way it seems to be a common practice to put the rear O2's in the front when installing headers.