Lately I've had some issues with my O2 sensors...the driver front threw a LOW VOLTAGE code a couple of weeks ago. When I A-Tapped it, sure enough, it was hanging around 0 voltage. When I was trying to replace the sensor, it was stuck in there pretty good, so we took some WD-40 to it and hit it with a hammer to try to shock it loose, but we still couldn't get it out. Strangely enough, after doing that, the O2 came back to life and started working perfectly! So I left it alone for a couple weeks and didn't get any more SES lights.

Until just recently. Yesterday, the car threw an INSUFFICIENT SWITCHING code, so I put A-Tap on it and reset the code, then immediately checked the voltage on the sensor and saw that it WAS switching like it should have been. I reset it and continued driving. Then today, I get the same thing...lots of historical INSUFFICIENT SWITCHING for the driver-side front (and even one for the passenger front)...but when I reset the code and watched the voltage on the sensors, AGAIN I saw switching. Obviously I can't judge whether it was "sufficient", but I saw both sensors doing it and both sensors were reading about the same voltage.

I'm not sure what's going on here...the O2s are about 16 months and 30,000 miles old. I think they were the Bosch/OEM sensor replacements. I'm just surprised they'd be going up this soon. I looked at the wiring for the driver front, and as much as I can SEE, it looks OK (you can only see it so far before it disappears into the engine bay). The sensor appears to be switching when I look at the voltage readings, even only a minute or two after the code was set.

Now, about a month or two ago I DID have a problem with a stuck injector on cylinder #7...not sure if it was stuck open or stuck shut, but it WAS bad enough to make the cylinder go completely dead and the car run like ****. Could that have caused a premature O2 sensor failure?

Also, could it possibly be fuel contamination? How would I even check for that??

These O2 sensors are over $100.00, so I don't want to go causally changing them if they're not bad. The Bosch OEM sensors have a one-year warranty, which I'm obviously over, but I thought these things were supposed to be good for 60K miles and I've got maybe half that on them.

Where do I look next? Thanks.

BTW, I DO have longtubes without cats...but I've had THEM for a couple years now. Occasionally threw the HEATER CIRCUIT codes, but never the INSUFFICIENT SWITCHING until just recently.

 

dont got with bosch, Only go with Ac Delco's, they last the longest

 

When I bought the Bosch sensor, it said "AC" on it.

Could just be coincidence...I had thought that Bosch made them for AC Delco or something.

 

Long tube headers = cooler O2s, the older they get
the more heat they need to get happy. Lot of
conflicting advice out there on what O2s last the
longest. I went and got Denso ones for the Corvette
rear position application, because Denso claims some
improved anti-fouling. These are higher heater wattage
than stockers as well. Can't tell you about the actual
service life because they're sitting in a box next to
the headers....

 

I too will be trying the denso's shortly. Im currently running bosch 13111 (vette rear sensors). My first set of bosches only lasted about a month before crapping out. I replpaced these and then the next set lasted about 4 months before throwing codes. My SES light had been on for about a month already (insufficient switching) and I pulled my bosch 13111's out a hit them with a propane torch for a couple minutes making them glow nice and cherry red. After they cooled down I put them back in the car and by the end of the day, my SES light had shut off. Ill probably keep cleaning my bosch this way as long as I can till I finally order some denso's, but nobody local carries them.

Oh, and as far as the AC Delco's being the best: Ite my opinion that they may be the most accurate, especially in the stock manifolds, but they are simply too weak to last once you go long tubes. My delco replacements did not last long at all.

 

Where can you get the Densos? How much more are they than the Bosches?

 

oxygen sensor.com

 

one word and plural

 

Is 234-4617 the right part number?

Do I need to switch both, or should I be OK with one Denso and one Bosch for the time being?

 

Weird...

Now I've got a Denso O2 on the way and I dunno if I even need it or not.

I drove to work today, then drove home. That's two ignition cycles. The SES light didn't come on, but I hooked up to Autotap/EFILive to see if there were any historicals or warning codes. NOTHING.

My switching issue is intermittent. And I'm not sure why.

Granted it was wet out last night and kinda cool, but I've driven in that kind of weather before and never seen a 1133 or 1153. And I've had these headers for a while now. Why NOW is it starting??

Coolant and oil level look about where I expected, so I don't think I have water or oil contamination on the sensor...always possible I got some bad gas, but I've never had trouble with that gas station before.

Or maybe it's just "on the way out" and still works sometimes. But it looks like it's switching fine now.

I guess I could just swap it out anyway...God knows, though. Don't see any carbon or hear any ticking from that side of the car, so I don't think it's an exhaust leak. I'll look at the wiring again next chance I get.

Why can't my car have REAL car problems like other people's?

 

Mine did that too. Colder weather and rain seem to cause an almost failing o2 sensor to go over the edge, but as soon as its nice out again, the code goes away and ses light goes out. Eventually, the SES will start to spend more time on than off, until the codes just dont ever go away

 

Not a hack, but I've got 112,000 miles on my stock O2's with LT's and they still function just fine. They're the factory Delcos.