GuitsBoy

iTrader: (4)

Who has changed your rich lean switchpoint settings before to deal with longtubes?

Anyone changed their closed loop proportional gain vs. o2 error in order to keep from setting insufficient switching codes?

Im still having a problem with insufficient switching no matter how many times or which brand o2 i go with.

Anyone have any info?

SSpeedracer

iTrader: (8)

I'm going to follow this thread closely..... if anyone has info to add.

I made several changes for idle. The only result I saw change was the switching frequency. I also changed switch points for partial throttle in order to "center" the O2's.

I want to change the switching amplitude to tighten up the AFR. How to make the O2s fluctuate between 100mV to 800mV?

SmokingWS6

iTrader: (1)

Do you have any hpl or excel logs of your car driving around normally? I'd like to see what your o2's are doing thats causing the code so often.

Have you tried changing the codes to report on 2nd error?

GuitsBoy

iTrader: (4)

Sure, it dosnt seem to be anything out of the ordinary. Theyve always been set to second error. The o2's on the car are new denso (vette rears) that are barely a week old.

Here's the excel CSV file: http://www.web-srv.com/~tony/tuning/bad_o2s.zip

Thanks,
-T

MeentSS02

iTrader: (11)

Oh, you mean the O2 sensors that everyone and their mom touts as the best solution to the LT problem with O2s...figures. It sounds like you may have gotten ahold of a bad pair. My Bosch 13111s have held up thus far...

As far as the original post goes, I'm not quite sure what to make of it all. So here's a TTT for ya.

GuitsBoy

iTrader: (4)

Two pair of bosch 13111's came to the same fate, although the second pair took a couple months. The first pair was acting the same as the denso's right out of the box. As were a pair of new delcos, and all 4 or my stock sensors. Ive probably thrown out a lot of perfectly good o2 sensors....

Thats going on 12 sensors in the 14 months ive had headers.

MeentSS02

iTrader: (11)

What kinda headers do you have again? Something is just not right here...my stockers lasted a year before crapping out, and the Bosch sensors have been in there for almost three months and not a peep.

GuitsBoy

iTrader: (4)

Jethot's. Ive been very careful tracking down any leaks and ive not used silicon or lead based products anywhere that would affect the sensors.

MeentSS02

iTrader: (11)

Hmmmmmmmm...I wish I could find some stats on the people with LT headers and their O2 sensors. I'm just wondering if there would be a significant difference between stainless and mild steel headers due to the heat transfer characteristics.

SmokingWS6

iTrader: (1)

Thats insane. Have you tried flashing in a new bone stock flash file? Tried swapping pcm's, check the harness at the pcm and o2 connection for corrision?

I'm on my same 13111's that i've had on since my header install last year.


I just looked at your csv file. Its hard to tell time since it didn't log it in seconds, however it looks like its swinging, but very slow and hangs really low for a second, also its switching fuel trim cells every time it swings even when rpm and tps was consistant. They seemed to be giving a decent reading in PE mode, rich too. lol. hmm. See if you can get somebody with hp tuners to scan it.

GuitsBoy

iTrader: (4)

I cut out the time for file size reasons. Right now is a tough time to post since im still tuning my cam with LTFTs disabled. Ill probably reenable is shortly then ill get you a real log file if you want to check it out. Its tough to tell if changine the parameters mentioned in the initial post have helped or hurt though.

Also, yes, all the connections are clean an oxidation free. I am using the vette rear type sensors, so i dont have o2 extentions nor any splices.

Peppershaker

Had simular problem with stock O2 and extensions. But was right after drove through some real deep water last summer after the hurricane Charley in Florida. Car didn't act up at all to begin with, but after sitting overnight went to start car next day and it would barely run. Suspected had something to do with moisture so jacked car up and pulled connectors apart on O2's and could see moisture in connectos and corrision starting to form. Couldn't figure how moisture would get in with sealed connector but got to looking at were wires come in the back side of connector aren't sealed real well. Took some sensor save silicone and sealed back side of connector and W-D 40 and sprayed terminal end of connector and cleaned contacts real good. then took hair dryier and dryed real good. Put everything back together and has worked fine for the last 10 months.

queso

Why not just delete codes 1133 and 1153? All they are telling you is that the O2's are not switching enough or have times in which they just "hang" high or low for more time that the PCM would like them to.

I had this same problem after my LT's (FLP's), and a pretty good heap of O2's going, both styles the Bosh Corvette rears and the F-body's. They would all work for a week or so. As soon as I drove at a steady low RPM for any extended amount of time they would come on. Also when driving during wet weather, the spray hitting the headers would cool them off and those codes would light up the SES light pretty quickly.

Before deleting, checked thoroughly for leaks and verified that they are switching properly at part throttle. After deleting, it eliminated the problem since the car PCM is now "desensitized" to the slightly-slower switching at low RPM. My LTFT's are dead on at -2.1 and -2.25 in closed loop and zero out immediately at WOT.

There are other codes in the PCM that will still tell you if they are inoperative or malfunction entirely...Problem fixed.

GuitsBoy

iTrader: (4)

Youre spot on about the extended low rpm driving, and cool / wet weather setting them off. I guess i just dont like the idea killing off the codes. If things continue this way, ill have no choice but to do just that. Thanks for the post.