Topic: P0133 code

[jws0318]

After all the problems i had early this year, the car has been running great the last couple of months, so i decided to put the hi-flow cat back on in place of the factory cat.  Since i've done that, I have been getting a P0133 code consistently, which is "O2 sensor circuit slow response (bank 1 sensor 1)".  If I understand this correctly, this is not the sensor that is on the cat itself - its a sensor prior to the cat?  Is it possible that swapping the factory cat for the hi-flow is causing a code, even though the changes are downline from the sensor that is indicated?

I know some people get codes with the hi-flow cat and they have them turned off through custom tuning.  Before my rebuild, i had the hi-flow cat on for 55k miles and never threw a code, but that was with the GM Roadster tune.  Since the rebuild, I have the GMPP tune now. 

Somehow, this must be tied to the hi-flow cat, but how would i correct it?  New sensor?  Custom tune to mask it?  Or is it all a coincidence and the P0133 code is something else entirely?

Thanks in advance for your thoughts...

[Arabas]

this code is the symptom. it is never good to cover the symptom. IMHO you have to see what the problem is (causing the symptom).
i never had a code with the hf cat without a tune P0133 must be a bad sensor or something the sensor is not reading outside the normal readings.
maybe you could get a new sensor, replace it and see if this solves everything

[TomatoSoup]

I recall that Solo moves the O2 sensor if you have a non-cat cat.  Could this be the same cause?

[scanner]

P0133 means the Pre-CAT O2 Sensor signal is not responding quickly enough. This is not the kind of thing you want to mask, it is not good for fuel economy or responsiveness to throttle inputs, or idle quality.  Seek the cause of this fault with a scantool that will show you O2 voltage.  Likely causes are exhaust leaks, even very small ones that pull in outside air during negative exhaust pressure.  Poor wiring routing, e.g. too close to other signals, wiring changes that added capacitance or inductance to the oe circuit, O2 location change relative to cylinder head, bad O2 heater or heater circuit. Lastly, the OBD EMS models the O2 sensor temperature before starting the diag, if the model is wrong because of a lower temp sensor the diag will run when the sensor is too cold and fail, i.e. P0133. One trial after checking for the above issues would be to drive mildly vs a little more agressive and watch the O2 performance with a scan tool at steady 5% throttle for ten second intervals. A sensor that is up to temp will respond rapidly to any throttle changes, the ECM expects significant changes in less that 100ms. Backpressure effects temperature.

Clear Skies.

      

[jws0318]

i have a scan tool, but im not sure if it reads O2 voltage or not - i'll check it out. 

I do have the Solo hiflow cat - the sensor is moved out a bit from the cat itself, but like i said, i had this cat on for 50k miles and never threw a code, although that was a different tune than i have now.  Is this the sensor that is on the hiflow cat, or a different one?  I'm not against buying a new sensor, but i want to make sure i replace the correct one if i'm going to do it.

Thanks

[scanner]

Oh No, don't go after a new sensor till you're sure everything else is good.  It could be the tune so ask the author what the diag test criteria are.  Any scan tool should be able to "see" bank one sensor one voltage.  Get a feel for it's reaction time, big swings oover 350mv from one update to the next mean that the sensor is reacting to O2 variation in the exhaust which is good.  If this looks good and your tuner can't give you the criteria for the diag get a new tuner, not a new sensor.

Clear Skies!

[tazz]

I think He's always around not always posting though and just PM him and he will usually answer your ?. 
If you do need a o2 sensor get it from http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&_rdc=1&item=330561164768&ru=http%3A%2F%2Fshop.ebay.com%3A80%2Fi.html%3F_from%3DR40%26_trksid%3Dp5197.m570.l1313%26_nkw%3D330561164768%26_sacat%3DSee-All-Categories%26_fvi%3D1&viewitem=

[MGar]

If I interpret the author correctly with "I do have the Solo hiflow cat - the sensor is moved out a bit from the cat itself", it sounds like you put the extender on the O2 sensor in the downpipe/hi flow cat, which is NOT where it belongs.

The extender is for the 2nd O2 sensor, not the one in the cat, and that would cause your problem.

[scanner]

So lets see, if it was not a machine, then the O2 DTC means shoot the messenger, right? Silly at best. O2 sensors are reporters, if you don't like the news replace the reporter? Silly, but then again it's your money, free country!

Clear Skies!    

[Gentleman Jack]

So lets see, if it was not a machine, then the O2 DTC means shoot the messenger, right? Silly at best. O2 sensors are reporters, if you don't like the news replace the reporter? Silly, but then again it's your money, free country!

Clear Skies!   

Scanner,

you know more about the computers than most and more about the real scan tools than anyone should ever have to know.  I think what the interpretation might be : shoot the messenger IF the messenger is not relaying the CORRECT message.  I don't know if O2 sensors are capable of relaying wrong / bad info, but I would think they could fail.

MGAR,
again, I don't know about the change in O2 placement, but that could be one of the issues, except the OP says he's had this on prior to some work being done to the engine, so I would guess (????) the parts would be in the right place?

GJ

[tazz]

When I popped a P0133 code it had to do with my stock cat being shot and after replacement I noticed the reading of the after cat (Bank 2) O2 sensor had a higher mv (700) reading as opposed to a lower mv (under 300) reading with the old cat since the clogged cat was causing the low reading.  
O2 sensors can fail and or become slow relaying the info to the ECM.
Now after my 2 pistons being replaced since the crack was allowing oil past in 2 cylinders I noticed a slight delay in the flip flop reading on the Precat (Bank 1) o2.  Not much but a slight reduction of the flip flop time non the less so I actually did spend $50 for a new sensor and the reaction time is quicker than with the old sensor since it does change rather quickly now.  So in my case the o2 sensor change did help but  JWS Issue is probably different and he should follow the other leads to see if that rectifies the issue before just changing the sensor.

[scanner]

i have a scan tool, but im not sure if it reads O2 voltage or not - i'll check it out. 

I do have the Solo hiflow cat - the sensor is moved out a bit from the cat itself, but like i said, i had this cat on for 50k miles and never threw a code, although that was a different tune than i have now.  Is this the sensor that is on the hiflow cat, or a different one?  I'm not against buying a new sensor, but i want to make sure i replace the correct one if i'm going to do it.

Thanks

P0133 is slow performance for the O2 sensor between the exhaust manifold and the CAT.   Sensors are numbered by their location relative to the engine by cylinder bank and sequencial position in the exhaust flow from engine to tailpipe. So you have bank 1, sensor 1 when you are the closest sensor to the cylinder 1. The O2 sensor after the CAT is Bank 1 Sensor 2.

The reason I recommend the steps I mentioned before is because anyone would be upset if their technician just threw a part at your car without diagnostic checks for other causes first.  The author of your tune should be consulted to see if their changes may have impacted the OBD, or if they have opinions on the cause of the DTC. 

Also have you cleared the DTC and roadtested the two ways I described?  One was driving grandma to church mode, the other drive style was late to see my sweetie mode. The test executes with a steady 5% throttle for several seconds after the O2 sensor temp model says it should be up to temp, if O2 is not actually up to temp it will perform more slowly.

I'm beginning to think every car enthusiast needs a family member or friend that is a tech.

  Clear Skies!

[Critterman]

never a truer statement said

I'm beginning to think every car enthusiast needs a family member or friend that is a tech.

But it is a lot like you can lead a horse to water, but you can't make him drink.

I for one appreciate your input here.
=

[Gentleman Jack]

I wish you were in my family.

[Critterman]

Only his advise is free GJ

[MGar]

MGAR,
again, I don't know about the change in O2 placement, but that could be one of the issues, except the OP says he's had this on prior to some work being done to the engine, so I would guess (????) the parts would be in the right place?

GJ

It was working fine prior to the high flow cat install.  The stock cat does not require an extender in the Bank 1 Sensor 2 location, but the high flow cat does.  If the installer made a mistake and put the extender in the Bank 1 Sensor 1 location, it would cause the error, and would only come along with the high flow cat install.  Given the mention of the "extra spacing" I would think the extender was placed in Bank 1 Sensor 1, instead of Bank 1 Sensor 2.

[jws0318]

I was not very clear in my earlier post - the extender is indeed in the Bank 1 Sensor 2 location.  This is where it was previously for many miles and it never threw any codes, but i had the GMRoadster tune on the car all that time.  When i took the car in for the cracked pistons repair, I removed the GMRoadster tune (as well as replaced the hiflow cat with the original factory cat) and had the dealership put the GMPP tune on the car while it was there.  I had no issues once I got the car back with any codes for 2 months.  When I put the hiflow cat back on a couple weeks ago, i have been throwing the code ever since. 

Since my "tuner" right now is the dealership, I'm guessing going to them with the code will be a dead end since I have put on the hiflow cat.

I need to figure out if my scan tool reads bank one sensor voltage.  I did drive the car this weekend and noticed that the code does not get loaded until i have driven a few miles - i made a couple of short trips and the code was never loaded.  It's one of those codes that doesn't show until the next engine cycle.

[Critterman]

Sounds like the code is showing when the cat reaches full temp.  you need to get a tool that can read the codes while you are driving and save it, so that you can monitor what is going on.

Did you check the extender wiring?  Perhaps it is damaged somehow, I would check it for continuity, missing insulation, and dirty connectors.  Start there anyone could cause you problems.

[Sol Asylum]

Is it possible that the sensor or the wire harness for it got damaged when you installed the hi flow cat?

[scanner]

 

[jws0318]

Is it possible that the sensor or the wire harness for it got damaged when you installed the hi flow cat?

I don't believe so - I did the swap with a friend - the only thing that comes to mind is he put some sort of lubricant on the thread of the sensor when he put it on - is it possible that it may somehow have gunked the sensor?  Maybe thats why it is providing a "slow response"?

Geez, I should have thought of that sooner.  Now that i think about it, i bet that is it.  Can the sensor be cleaned, or is it not worth the trouble?

I am still going to hook up the scan tool this afternoon when i get home, but assuming that pans out fine...

[miller11386]

It is probably anti-seize he put on the O2 sensor.


I have had a HF cat and the O2 extender and have not had any problems.

I even drilled another hole in the solo HF cat to get my 2nd wideband O2 in for my AFR gauge.

If the sensor is "slow to respond" I would think the sensor may be failing? I have heard they do funny things when they are on the brink of death

[jws0318]

Just to clear up the thread, after monitoring the O2 sensor, it turns out the sensor was on its way out.   I replaced the sensor 500 miles ago, and so far, all is good. 

thanks again to everyone for their help!